subsonic

English Thesaurus

1. (of speed) less than that of sound in a designated medium (adj.all)

antonym	:	sonic, transonic,
definition	:	(of speed) having or caused by speed approximately equal to that of sound in air at sea level (adj.all)

antonym	:	supersonic,
definition	:	(of speed) greater than the speed of sound in a given medium (especially air) (adj.all)

antonym	:	sonic, transonic,
definition	:	(of speed) having or caused by speed approximately equal to that of sound in air at sea level (adj.all)

antonym	:	supersonic,
definition	:	(of speed) greater than the speed of sound in a given medium (especially air) (adj.all)