polyptoton (plural polyptota)
ORIGIN: Late Latin, from Greek polyptōton, neuter of polyptōtos using many cases of the same word, from poly- + ptōtos (from piptein to fall, influenced in meaning by Greek ptōsis case)
DEFINITION: the rhetorical repetition of a word in a different case, inflection, or voice in the same sentence
SENTENCE: The most common example I’ve seen of polyptoton in English is Tennyson’s “my own heart’s heart, and my ownest own.”
WHY IT’S INTERESTING: I happen to like words that originated from Greek, and this is no exception. The word also has a slightly odd pronunciation: the accent is on the third syllable, not the second.