diff --git a/NEWS b/NEWS
index c50079e42..e7973d198 100644
--- a/NEWS
+++ b/NEWS
@@ -227,6 +227,10 @@ New in spot 2.4.4.dev (net yet released)
   - The "product-states" property of automata is now accessible via
     spot.twa.get_product_states() and spot.set.get_product_states().
 
+  - twa_word instances can be displayed as SVG pictures, with one
+    signal per atomic proposition.  For some examples, see the use of
+    the show() method in https://spot.lrde.epita.fr/ipynb/word.html
+
   Deprecation notices:
 
   (These functions still work but compilers emit warnings.)
diff --git a/python/spot/__init__.py b/python/spot/__init__.py
index 1a4856264..b8064e6d4 100644
--- a/python/spot/__init__.py
+++ b/python/spot/__init__.py
@@ -1010,3 +1010,92 @@ def show_mp_hierarchy(cl):
     return SVG(mp_hierarchy_svg(cl))
 
 formula.show_mp_hierarchy = show_mp_hierarchy
+
+@_extend(twa_word)
+class twa_word:
+    def as_svg(self):
+        """
+        Build an SVG picture representing the word as a collection of
+        signals for each atomic proposition.
+        """
+        # Get the list of atomic proposition used
+        sup = buddy.bddtrue
+        for cond in list(self.prefix) + list(self.cycle):
+            sup = sup & buddy.bdd_support(cond)
+        ap = []
+        while sup != buddy.bddtrue:
+            a = buddy.bdd_var(sup)
+            ap.append(a)
+            sup = buddy.bdd_high(sup)
+
+        # Prepare canvas
+        psize = len(self.prefix)
+        csize = len(self.cycle)
+        d = {
+            'endprefix': 50 * psize,
+            'endcycle': 50 * (psize + csize),
+            'w': 50 * (psize + csize * 2),
+            'height': 50 * len(ap),
+            'height2': 50 * len(ap) + 10,
+            'h3': 50 * len(ap) + 12,
+            'bgcolor': '#f4f4f4',
+            'bgl': 'stroke="white" stroke-width="4"',
+            'bgt': 'stroke="white" stroke-width="1"',
+            'txt': 'text-anchor="start" font-size="20"',
+            'red': 'stroke="#ff0000" stroke-width="2"',
+            'sml': 'text-anchor="start" font-size="10"'
+            }
+        txt = '''
+<svg height="{h3}" width="{w}" xmlns="http://www.w3.org/2000/svg" version="1.1">
+<rect x="0" y="0" width="{w}" height="{height}" fill="{bgcolor}"/>
+<line x1="{endprefix}" y1="0" x2="{endprefix}" y2="{height}"
+      stroke="white" stroke-width="4"/>
+<line x1="{endcycle}" y1="0" x2="{endcycle}" y2="{height}"
+      stroke="white" stroke-width="4"/>
+'''.format(**d)
+
+        # Iterate over all used atomic propositions, and fill each line
+        l = list(self.prefix) + list(self.cycle) + list(self.cycle)
+        bd = self.get_dict()
+        for ypos, a in enumerate(ap):
+            pa = buddy.bdd_ithvar(a)
+            na = buddy.bdd_nithvar(a)
+            name = bdd_format_formula(bd, pa)
+            # Whether the last state was down (-1), up (1), or unknown (0)
+            last = 0
+            txt += ('<line x1="0" y1="{y}" x2="{w}" y2="{y}" {bgl}/>'
+                    .format(y=ypos*50, **d))
+            txt += ('<text x="{x}" y="{y}" {txt}>{name}</text>'
+                    .format(x=3, y=ypos*50+30, name=name, **d))
+            for xpos, step in enumerate(l):
+                if buddy.bdd_implies(step, pa):
+                    cur = 1
+                elif buddy.bdd_implies(step, na):
+                    cur = -1
+                else:
+                    cur = 0
+                txt += ('<line x1="{x}" y1="{y1}" x2="{x}" y2="{y2}" {bgt}/>'
+                        .format(x=(xpos+1)*50, y1=ypos*50, y2=ypos*50+50, **d))
+                if cur != 0:
+                    if last == -cur:
+                        txt += \
+                        ('<line x1="{x}" y1="{y1}" x2="{x}" y2="{y2}" {red}/>'
+                             .format(x=xpos*50, y1=ypos*50+5,
+                                     y2=ypos*50+45, **d))
+                    txt += \
+                    ('<line x1="{x1}" y1="{y}" x2="{x2}" y2="{y}" {red}/>'
+                         .format(x1=xpos*50, x2=(xpos+1)*50,
+                                 y=ypos*50+25-20*cur, **d))
+                last = cur
+        if psize > 0:
+            txt += '<text x="0" y="{height2}" {sml}>prefix</text>'.format(**d)
+        txt += '''<text x="{endprefix}" y="{height2}" {sml}>cycle</text>
+<text x="{endcycle}" y="{height2}" {sml}>cycle</text>'''.format(**d)
+        return txt + '</svg>'
+
+    def show(self):
+        """
+        Display the word as an SVG picture of signals.
+        """
+        from IPython.display import SVG
+        return SVG(self.as_svg())
diff --git a/tests/python/word.ipynb b/tests/python/word.ipynb
index 2ee85888a..4bc52263c 100644
--- a/tests/python/word.ipynb
+++ b/tests/python/word.ipynb
@@ -15,7 +15,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.5.3"
+   "version": "3.6.4"
   },
   "name": ""
  },
@@ -47,7 +47,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "aut = spot.translate('G(Fa <-> XXb)'); aut"
+      "aut = spot.translate('!a & G(Fa <-> XXb)'); aut"
      ],
      "language": "python",
      "metadata": {},
@@ -63,150 +63,121 @@
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-        "<!-- 3&#45;&gt;5 -->\n",
-        "<g id=\"edge12\" class=\"edge\"><title>3&#45;&gt;5</title>\n",
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-        "<g id=\"edge13\" class=\"edge\"><title>4&#45;&gt;3</title>\n",
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-        "</g>\n",
-        "<!-- 6&#45;&gt;6 -->\n",
-        "<g id=\"edge16\" class=\"edge\"><title>6&#45;&gt;6</title>\n",
+        "<g id=\"edge11\" class=\"edge\"><title>4&#45;&gt;4</title>\n",
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+        "<!-- 5&#45;&gt;4 -->\n",
+        "<g id=\"edge12\" class=\"edge\"><title>5&#45;&gt;4</title>\n",
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+        "<text text-anchor=\"start\" x=\"363\" y=\"-101.8\" font-family=\"Lato\" font-size=\"14.00\">!a &amp; b</text>\n",
+        "</g>\n",
         "</g>\n",
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7fdf783f0510> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7fb74c39da80> >"
        ]
       }
      ],
@@ -235,11 +206,11 @@
        "text": [
         "Prefix:\n",
         "  0\n",
-        "  |  a\n",
+        "  |  !a\n",
         "  1\n",
         "  |  a\n",
         "Cycle:\n",
-        "  3\n",
+        "  2\n",
         "  |  a & b\t{0}"
        ]
       }
@@ -267,7 +238,7 @@
        "output_type": "stream",
        "stream": "stdout",
        "text": [
-        "a\n",
+        "!a\n",
         "{0}\n"
        ]
       }
@@ -295,12 +266,47 @@
        "output_type": "pyout",
        "prompt_number": 5,
        "text": [
-        "a; a; cycle{a & b}"
+        "!a; a; cycle{a & b}"
        ]
       }
      ],
      "prompt_number": 5
     },
+    {
+     "cell_type": "markdown",
+     "metadata": {},
+     "source": [
+      "A word can be represented as a collection of signals (one for each atomic proposition).  The cycle part is shown twice."
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "word.show()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "metadata": {},
+       "output_type": "pyout",
+       "prompt_number": 6,
+       "svg": [
+        "<svg height=\"112\" version=\"1.1\" width=\"200\" xmlns=\"http://www.w3.org/2000/svg\">\n",
+        "<rect fill=\"#f4f4f4\" height=\"100\" width=\"200\" x=\"0\" y=\"0\"/>\n",
+        "<line stroke=\"white\" stroke-width=\"4\" x1=\"100\" x2=\"100\" y1=\"0\" y2=\"100\"/>\n",
+        "<line stroke=\"white\" stroke-width=\"4\" x1=\"150\" x2=\"150\" y1=\"0\" y2=\"100\"/>\n",
+        "<line stroke=\"white\" stroke-width=\"4\" x1=\"0\" x2=\"200\" y1=\"0\" y2=\"0\"/><text font-size=\"20\" text-anchor=\"start\" x=\"3\" y=\"30\">a</text><line stroke=\"white\" stroke-width=\"1\" x1=\"50\" x2=\"50\" y1=\"0\" y2=\"50\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"0\" x2=\"50\" y1=\"45\" y2=\"45\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"100\" x2=\"100\" y1=\"0\" y2=\"50\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"50\" x2=\"50\" y1=\"5\" y2=\"45\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"50\" x2=\"100\" y1=\"5\" y2=\"5\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"150\" x2=\"150\" y1=\"0\" y2=\"50\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"100\" x2=\"150\" y1=\"5\" y2=\"5\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"200\" x2=\"200\" y1=\"0\" y2=\"50\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"150\" x2=\"200\" y1=\"5\" y2=\"5\"/><line stroke=\"white\" stroke-width=\"4\" x1=\"0\" x2=\"200\" y1=\"50\" y2=\"50\"/><text font-size=\"20\" text-anchor=\"start\" x=\"3\" y=\"80\">b</text><line stroke=\"white\" stroke-width=\"1\" x1=\"50\" x2=\"50\" y1=\"50\" y2=\"100\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"100\" x2=\"100\" y1=\"50\" y2=\"100\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"150\" x2=\"150\" y1=\"50\" y2=\"100\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"100\" x2=\"150\" y1=\"55\" y2=\"55\"/><line stroke=\"white\" stroke-width=\"1\" x1=\"200\" x2=\"200\" y1=\"50\" y2=\"100\"/><line stroke=\"#ff0000\" stroke-width=\"2\" x1=\"150\" x2=\"200\" y1=\"55\" y2=\"55\"/><text font-size=\"10\" text-anchor=\"start\" x=\"0\" y=\"110\">prefix</text><text font-size=\"10\" text-anchor=\"start\" x=\"100\" y=\"110\">cycle</text>\n",
+        "<text font-size=\"10\" text-anchor=\"start\" x=\"150\" y=\"110\">cycle</text></svg>"
+       ],
+       "text": [
+        "<IPython.core.display.SVG object>"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
     {
      "cell_type": "markdown",
      "metadata": {},
@@ -323,13 +329,13 @@
        "output_type": "stream",
        "stream": "stdout",
        "text": [
-        "a\n",
+        "!a\n",
         "a\n",
         "a & b\n"
        ]
       }
      ],
-     "prompt_number": 6
+     "prompt_number": 7
     },
     {
      "cell_type": "markdown",
@@ -351,13 +357,13 @@
       {
        "metadata": {},
        "output_type": "pyout",
-       "prompt_number": 7,
+       "prompt_number": 8,
        "text": [
-        "cycle{a & b}"
+        "!a; cycle{a & b}"
        ]
       }
      ],
-     "prompt_number": 7
+     "prompt_number": 8
     },
     {
      "cell_type": "markdown",
@@ -378,13 +384,13 @@
       {
        "metadata": {},
        "output_type": "pyout",
-       "prompt_number": 8,
+       "prompt_number": 9,
        "text": [
-        "cycle{a & b}"
+        "!a; cycle{a & b}"
        ]
       }
      ],
-     "prompt_number": 8
+     "prompt_number": 9
     },
     {
      "cell_type": "markdown",
@@ -414,14 +420,14 @@
        ]
       }
      ],
-     "prompt_number": 9
+     "prompt_number": 10
     },
     {
      "cell_type": "code",
      "collapsed": false,
      "input": [
       "# make sure that we can parse a word back after it has been printed\n",
-      "spot.parse_word(str(spot.parse_word('a;b&a;cycle{!a&!b}')))"
+      "w = spot.parse_word(str(spot.parse_word('a;b&a;cycle{!a&!b;!a&b}'))); w"
      ],
      "language": "python",
      "metadata": {},
@@ -429,13 +435,41 @@
       {
        "metadata": {},
        "output_type": "pyout",
-       "prompt_number": 10,
+       "prompt_number": 11,
        "text": [
-        "a; a & b; cycle{!a & !b}"
+        "a; a & b; cycle{!a & !b; !a & b}"
        ]
       }
      ],
-     "prompt_number": 10
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "w.show()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "metadata": {},
+       "output_type": "pyout",
+       "prompt_number": 12,
+       "svg": [
+        "<svg height=\"112\" version=\"1.1\" width=\"300\" xmlns=\"http://www.w3.org/2000/svg\">\n",
+        "<rect fill=\"#f4f4f4\" height=\"100\" width=\"300\" x=\"0\" y=\"0\"/>\n",
+        "<line stroke=\"white\" stroke-width=\"4\" x1=\"100\" x2=\"100\" y1=\"0\" y2=\"100\"/>\n",
+        "<line stroke=\"white\" stroke-width=\"4\" x1=\"200\" x2=\"200\" y1=\"0\" y2=\"100\"/>\n",
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+        "<text font-size=\"10\" text-anchor=\"start\" x=\"200\" y=\"110\">cycle</text></svg>"
+       ],
+       "text": [
+        "<IPython.core.display.SVG object>"
+       ]
+      }
+     ],
+     "prompt_number": 12
     },
     {
      "cell_type": "markdown",
@@ -453,7 +487,7 @@
      "language": "python",
      "metadata": {},
      "outputs": [],
-     "prompt_number": 11
+     "prompt_number": 13
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     {
      "cell_type": "code",
@@ -467,7 +501,7 @@
       {
        "metadata": {},
        "output_type": "pyout",
-       "prompt_number": 12,
+       "prompt_number": 14,
        "svg": [
         "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n",
         "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\"\n",
@@ -545,17 +579,17 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7fdf783f0e40> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7fb74c39d990> >"
        ]
       }
      ],
-     "prompt_number": 12
+     "prompt_number": 14
     },
     {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "The rest of this pages tests some syntax errors, you (humans) may skip it, but the test suite will not."
+      "The rest of this page tests some syntax errors, you (humans) may skip it, but the test suite will not."
      ]
     },
     {
@@ -576,7 +610,7 @@
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       }
      ],
-     "prompt_number": 13
+     "prompt_number": 15
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@@ -596,7 +630,7 @@
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-     "prompt_number": 14
+     "prompt_number": 16
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@@ -616,7 +650,7 @@
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      ],
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+     "prompt_number": 17
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@@ -636,7 +670,7 @@
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      ],
-     "prompt_number": 16
+     "prompt_number": 18
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     {
      "cell_type": "code",
@@ -648,7 +682,7 @@
      "language": "python",
      "metadata": {},
      "outputs": [],
-     "prompt_number": 17
+     "prompt_number": 19
     },
     {
      "cell_type": "code",
@@ -667,13 +701,13 @@
        "traceback": [
         "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
         "\u001b[0;31mRuntimeError\u001b[0m                              Traceback (most recent call last)",
-        "\u001b[0;32m<ipython-input-18-971829bb8f5f>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m# ... as long as this word is not printed.\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mw\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-        "\u001b[0;32m/home/adl/git/spot/python/spot/impl.py\u001b[0m in \u001b[0;36m__str__\u001b[0;34m(self)\u001b[0m\n\u001b[1;32m   4160\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   4161\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0m__str__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;34m->\u001b[0m \u001b[0;34m\"std::string\"\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m-> 4162\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0m_impl\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mtwa_word___str__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   4163\u001b[0m \u001b[0mtwa_word_swigregister\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0m_impl\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mtwa_word_swigregister\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   4164\u001b[0m \u001b[0mtwa_word_swigregister\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mtwa_word\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m<ipython-input-20-9968db49e707>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m# ... as long as this word is not printed.\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mw\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
+        "\u001b[0;32m/home/adl/git/spot/python/spot/impl.py\u001b[0m in \u001b[0;36m__str__\u001b[0;34m(self)\u001b[0m\n\u001b[1;32m   4922\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   4923\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0m__str__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;34m->\u001b[0m \u001b[0;34m\"std::string\"\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m-> 4924\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0m_impl\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mtwa_word___str__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   4925\u001b[0m \u001b[0mtwa_word_swigregister\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0m_impl\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mtwa_word_swigregister\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   4926\u001b[0m \u001b[0mtwa_word_swigregister\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mtwa_word\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
         "\u001b[0;31mRuntimeError\u001b[0m: a twa_word may not have an empty cycle"
        ]
       }
      ],
-     "prompt_number": 18
+     "prompt_number": 20
     }
    ],
    "metadata": {}