(biology) A lack of correspondence between biomolecules or body parts (e.g., proteins, tissues, bones, limbs) that reflects a difference in origin.
(grammar) The property of a word or phrase that does not describe itself.
The words ultrashort and onomatopoeia display heterology: ultrashort might be called short but is not an ultrashort word, and onomatopoeia is not an onomatopoeic word.