undulate [ verb uhn-juh-leyt, uhn-dyuh-, -duh-; adjective uhn-juh-lit, -leyt, uhn-dyuh-, -duh- ]
verb (used without object), un·du·lat·ed, un·du·lat·ing.
1. to move with a sinuous or wavelike motion; display a smooth rising-and-falling or side-to-side alternation of movement: The flag undulates in the breeze.
2. to have a wavy form or surface; bend with successive curves in alternate directions.
3. (of a sound) to rise and fall in pitch: the wail of a siren undulating in the distance.
verb (used with object), un·du·lat·ed, un·du·lat·ing.
4. to cause to move in waves.
5. to give a wavy form to.
6. Also un·du·lat·ed. having a wavelike or rippled form, surface, edge, etc.; wavy.
wobble, billow, swell, flow, surge, swing, ripple, wave, heave, roll, oscillate
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Origin: 1650–60; < Latin undulātus waved, equivalent to und(a) wave + -ul(a) -ule + -ātus -ate
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