heteronym

from WordNet (r) 3.0 (2006)

heteronym
    n 1: two words are heteronyms if they are spelled the same way
         but differ in pronunciation; "the word `bow' is an example
         of a heteronym"

from The Collaborative International Dictionary of English v.0.48

Heteronym \Het"er*o*nym\, n.
   That which is heteronymous; a thing having a different name
   or designation from some other thing; -- opposed to homonym.
   [1913 Webster]

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