- (billow) a large sea wave
- (billow) rise up as if in waves; "smoke billowed up into the sky"
- (billow) move with great difficulty; "The soldiers billowed across the muddy riverbed"
- (billow) balloon: become inflated; "The sails ballooned"
- (Billow) In mathematics and science, a wave is a disturbance that travels through space and time, usually by the transfer of energy. Waves are described by a wave equation that can take on many forms depending on the type of wave. ...