The quality or state of being a heteronym; the phenomenon of words having identical spelling but different pronunciations and meanings.
From heteronym plus -y (noun suffix), creating an abstract noun for the linguistic phenomenon where words share spelling but differ in meaning and sound.
Heteronymy is what makes English ridiculously difficult: 'tear' can mean sadness or the action of ripping, pronounced totally differently, and you have to rely on context to understand which one the speaker means!
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