/ Dictionary / Index L lambdacism: Meaning and Definition of Find definitions for: lamb•da•cism Pronunciation: (lam'du-siz"um), [key] — n. Phonet. excessive use of the sound l, its misarticulation, or its substitution for the sound r. Cf. lallation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: lambdacism (Thesaurus) lambda lambda particle Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language