/ Dictionary / Index R radiosonde: Meaning and Definition of Find definitions for: ra•di•o•sonde Pronunciation: (rā'dē-ō-sond"), [key] — n. Meteorol. an instrument that is carried aloft by a balloon to send back information on atmospheric temperature, pressure, and humidity by means of a small radio transmitter. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. radiosodium radio source Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language