from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of or relating to aerodynamic flow or flight conditions at speeds near the speed of sound.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. just below, or just above the speed of sound
- adj. passing from subsonic to supersonic, or vice versa
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. (of speed) having or caused by speed approximately equal to that of sound in air at sea level
tran(s)- + sonic.(American Heritage® Dictionary of the English Language, Fourth Edition)
trans- + sonic (Wiktionary)