[ verb uhn-juh-leyt, uhn-dyuh-, -duh-; adjective uhn-juh-lit, -leyt, uhn-dyuh-, -duh- ]
/ verb ˈʌn dʒəˌleɪt, ˈʌn dyə-, -də-; adjective ˈʌn dʒə lɪt, -ˌleɪt, ˈʌn dyə-, -də- /

WATCH NOW: What Do "Undulate" And Flag Day Have In Common?

WATCH NOW: What Do "Undulate" And Flag Day Have In Common?

Waves undulate, flags undulate ... and in this video both of those meanings work together to create the perfect image. Watch our favorite Word of the Day illustrator bring the word to life.


verb (used without object), un·du·lat·ed, un·du·lat·ing.

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.
to have a wavy form or surface; bend with successive curves in alternate directions.
(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.

to cause to move in waves.
to give a wavy form to.


Also un·du·lat·ed. having a wavelike or rippled form, surface, edge, etc.; wavy.

Origin of undulate

1650–60; < Latin undulātus waved, equivalent to und(a) wave + -ul(a) -ule + -ātus -ate1


un·du·la·tor, nounnon·un·du·late, adjectivenon·un·du·lat·ing, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for undulate

British Dictionary definitions for undulate

/ (ˈʌndjʊˌleɪt) /


to move or cause to move in waves or as if in waves
to have or provide with a wavy form or appearance

adjective (ˈʌndjʊlɪt, -ˌleɪt) undulated

having a wavy or rippled appearance, margin, or forman undulate leaf

Derived forms of undulate

undulator, noun

Word Origin for undulate

C17: from Latin undulātus, from unda a wave
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012