1. subsonic - Noun
2. subsonic - Adjective
(of speed) less than that of sound in a designated medium
Source: WordNetaircraft flying at subsonic speeds Source: Internet
A key trait of ramjet engines is that combustion is done at subsonic speeds. Source: Internet
Aft-swept wing settings are used in high subsonic and supersonic flight. Source: Internet
Although they moved quickly in flight, early re-entry systems slowed dramatically once they reached the lower atmosphere, The Polaris W58 warhead was subsonic. Source: Internet
After shock wave detachment, an entry vehicle must carry significantly more shocklayer gas around the leading edge stagnation point (the subsonic cap). Source: Internet
As of March 2007, the GDF has been reconfigured to operate a cold gas gun for subsonic CEV capsule aerodynamics. Source: Internet