Main Entry: ¹bil·low

Pronunciation: \ˈbi-(ˌ)lō\

Function: noun

Etymology: Old Norse bylgja; akin to Old High German balg bag — more at belly

Date: 1552

1 : wave; especially : a great wave or surge of water
2 : a rolling mass (as of flame or smoke) that resembles a high wave

— bil·lowy \ˈbi-lə-wē\ adjective