/ Dictionary / Index M mean free path: Meaning and Definition of Find definitions for: mean' free' path' Pronunciation: [key] the average distance that a particle travels between successive collisions with other particles. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. meandrous meanie Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language