definition of billow
Definition of billow. 1  1 : wave; especially : a great wave or surge of water the rolling billows of the sea. 2  2 : a rolling mass (as of flame or smoke) that resembles a high wave Billows of smoke poured out of the building. billows of fog.
Webster Dictionary(0.00 / 0 votes)Rate this definition: 1  Billow(noun) a great wave or surge of the sea or other water, caused usually by violent wind. 2  Billow(noun) a great wave or flood of anything. 3  Billow(verb) to surge; to rise and roll in waves or surges; to undulate.