Breadcrumb Home > Dictionary > Index T transponder: Meaning and Definition of Find definitions for: tran•spon•der Pronunciation: (tran-spon'dur), [key] — n. a radio, radar, or sonar transceiver that automatically transmits a signal upon reception of a designated incoming signal. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: transponder (Thesaurus) transplantee transponible ✖ Related Content Daily Word Quiz: donnybrook Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language