/ Dictionary / Index P ptomaine: Meaning and Definition of Find definitions for: pto•maine Pronunciation: (tō'mān, tō-mān'), [key] — n. any of a class of foul-smelling nitrogenous substances produced by bacteria during putrefaction of animal or plant protein: formerly thought to be toxic. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ptomaine (Thesaurus) Ptolemy II ptomaine poisoning Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language