Billow

Part of speech: noun (n.)

1. A great wave or surge of the sea or other water, caused usually by violent wind. Whom the winds waft where'er the billows roll. Cowper.

2. A great wave or flood of anything. Milton.

Part of speech: verb (v.)

To surge; to rise and roll in waves or surges; to undulate. "The billowing snow." Prior.