/ Dictionary / Index U undercarriage: Meaning and Definition of Find definitions for: un•der•car•riage Pronunciation: (un'dur-kar"ij), [key] — n. the supporting framework underneath a vehicle, as an automobile or trailer; the structure to which the wheels, tracks, or the like are attached or fitted. the portions of an aircraft that are below the body. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: undercarriage (Thesaurus) undercard undercast Related Content Daily Word Quiz: inutiae Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language