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[v. uhn-juh-leyt, uhn-dyuh-, -duh-; adj. uhn-juh-lit, -leyt, uhn-dyuh-, -duh-] /v. ˈʌn dʒəˌleɪt, ˈʌn dyə-, -də-; adj. ˈʌn dʒə lɪt, -ˌleɪt, ˈʌn dyə-, -də-/
verb (used without object), undulated, undulating.
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), undulated, undulating.
to cause to move in waves.
to give a wavy form to.
Also, undulated. 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
Related forms
undulator, noun
nonundulate, adjective
nonundulating, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for undulate
  • The plesiosaur, being a reptile, wouldn't undulate but move from side to side.
  • Every time a major storm blew in from the north, the sea would undulate under our camp, and the ice would break up all around us.
  • The roof is an ocean swell thickly rippled with ceramic tiles that undulate in colors as well as curves.
  • Tents of many kinds and sizes undulate across the dunes.
  • The rice stalks, newly planted, undulate in the breeze as they stretch toward the sun.
  • They slowly undulate around her, shivering to generate warmth.
  • When they occur, they cause the ground to undulate and shake, perhaps violently.
  • The facades undulate with alternating swell-fronts and rectilinear bays.
  • The bulb-coats are brown or gray, thin, with horizontal undulate reticulation in vertical rows.
  • Leaf margins are undulate with small teeth that are close set, and stick straight out from the leaf blade.
British Dictionary definitions for undulate


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)
having a wavy or rippled appearance, margin, or form: an undulate leaf
Derived Forms
undulator, noun
Word Origin
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
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Word Origin and History for undulate

1660s, from undulation. Related: undulated, undulating.

Online Etymology Dictionary, © 2010 Douglas Harper
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