Internally ambiguous words?

[David Bowie]

A student just asked me if there is a name for words that are internally
structurally ambiguous, like 'unbuttonable', which can mean 'not able to be
buttoned' or 'able to be unbuttoned', depending on whether it's analyzed as
un+buttonable or unbutton+able. Anybody on this list know what the term
might be, if one exists?

(The reactions to the students in the class on the most natural meaning of
the word was interesting, and made me wonder what might condition different
readings of the same word in the same context. Yet *another* thing to put on
my 'Things that would be cool to look into if i had time, but i don't' list.
*sigh* )

David Bowie                                       Department of English
Assistant Professor                            Brigham Young University
db.list at pmpkn.net              http://humanities.byu.edu/faculty/bowied
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