[css-text] Clarify overflow-wrap: break-word <https://lists.w3.org/Archives/Public/www-style/2015Jun/0100.html>

Author: kojiishi

css-text/Overview.bs

@@ -1297,7 +1297,8 @@ Canonical order: N/A
       introduced by ''word-break: keep-all'' may be relaxed to match ''word-break: normal''
       if there are no otherwise-acceptable break points in the line.</dd>
     <dt><dfn>break-word</dfn></dt>
-    <dd>An unbreakable "word" may be broken at an arbitrary point if
+    <dd>An otherwise unbreakable sequence of <a>characters</a>
+      may be broken at an arbitrary point if
       there are no otherwise-acceptable break points in the line.
       Shaping characters are still shaped as if the word were not
       broken, and grapheme clusters must stay together as one unit.