/ Dictionary / Index U ultrasonics: Meaning and Definition of Find definitions for: ul•tra•son•ics Pronunciation: (ul"tru-son'iks), [key] — n. (used with a sing. v.) the branch of science that deals with the effects of sound waves above human perception. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ultrasonic ultrasonography Related Content Daily Word Quiz: philanthropy Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language