n. & v.
n. 1 a sensation caused in the ear by the vibration of the surrounding air or other medium. 2 a vibrations causing this sensation. b similar vibrations whether audible or not. 3 what is or may be heard. 4 an idea or impression conveyed by words (don't like the sound of that). 5 mere words (sound and fury). 6 (in full musical sound) sound produced by continuous and regular vibrations (opp. NOISE n. 3). 7 any of a series of articulate utterances (vowel and consonant sounds). 8 music, speech, etc., accompanying a film or other visual presentation. 9 (often attrib.) broadcasting by radio as distinct from television.
v. 1 intr. & tr. emit or cause to emit sound. 2 tr. utter or pronounce (sound a note of alarm). 3 intr. convey an impression when heard (you sound worried). 4 tr. give an audible signal for (an alarm etc.). 5 tr. test (the lungs etc.) by noting the sound produced. 6 tr. cause to resound; make known (sound their praises). sound barrier the high resistance of air to objects moving at speeds near that of sound. sound effect a sound other than speech or music made artificially for use in a play, film, etc. sound engineer an engineer dealing with acoustics etc. sound-hole an aperture in the belly of some stringed instruments. sound off talk loudly or express one's opinions forcefully. sound-post a small prop between the belly and back of some stringed instruments. sound shift see SHIFT n. 6. sound spectrograph an instrument for analysing sound into its frequency components. sound wave a wave of compression and rarefaction, by which sound is propagated in an elastic medium, e.g. air. soundless adj. soundlessly adv. soundlessness n.
[ ME f. AF soun, OF son (n.), AF suner, OF soner (v.) f. L sonus ]