Billow (&unr_;), n. [Cf. Icel. bylgja billow, Dan. bölge, Sw. bölja; akin to MHG. bulge billow, bag, and to E. bulge. See Bulge.] 1. A great wave or surge of the sea or other water, caused usually by violent wind.
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Whom the winds waft where'er the billows roll. Cowper.
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2. A great wave or flood of anything. Milton.
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