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adjective un·du·late \ˈən-jə-lət, ˈən-dyə-, ˈən-də-, -ˌlāt\

Definition of undulate

  1. :  having a wavy surface, edge, or markings <the undulate margin of a leaf>

Variants of undulate



play \-ˌlā-təd\

Origin and Etymology of undulate

Latin undulatus, from *undula, diminutive of unda wave — more at water

First Known Use: 1658



verb un·du·late \-ˌlāt\

Simple Definition of undulate

  • : to move or be shaped like waves

Source: Merriam-Webster's Learner's Dictionary

Full Definition of undulate



  1. intransitive verb
  2. 1 :  to form or move in waves :  fluctuate

  3. 2 :  to rise and fall in volume, pitch, or cadence

  4. 3 :  to present a wavy appearance

  5. transitive verb
  6. :  to cause to move in a wavy, sinuous, or flowing manner

Did You Know?

Undulate and "inundate" are word cousins, sharing "unda," the Latin word for "wave," as their common ancestor. No surprise there. But would you have guessed that "abound," "surround," and "redound" are also "unda" offspring? The connection between "unda" and these words is easier to see when you learn that at some point in their early histories each of them essentially had the meaning of "to overflow"-a meaning that "inundate" still carries, along with its "overwhelm" sense.

Origin and Etymology of undulate

Late Latin undula small wave, from Latin *undula

First Known Use: 1664

Synonym Discussion of undulate

swing, wave, flourish, brandish, thrash mean to wield or cause to move to and fro or up and down. swing implies regular or uniform movement <swing the rope back and forth>. wave usually implies smooth or continuous motion <waving the flag>. flourish suggests vigorous, ostentatious, graceful movement <flourished the winning lottery ticket>. brandish implies threatening or menacing motion <brandishing a knife>. thrash suggests vigorous, abrupt, violent movement <an infant thrashing his arms about>.

swing, sway, oscillate, vibrate, fluctuate, waver, undulate mean to move from one direction to its opposite. swing implies a movement of something attached at one end or one side <the door suddenly swung open>. sway implies a slow swinging or teetering movement <trees swaying in the breeze>. oscillate stresses a usually regular alternation of direction <an oscillating fan>. vibrate suggests the rapid oscillation of an elastic body under stress or impact <the vibrating strings of a piano>. fluctuate suggests constant irregular changes of level, intensity, or value <fluctuating interest rates>. waver stresses irregular motion suggestive of reeling or tottering <the exhausted runner wavered before collapsing>. undulate suggests a gentle wavelike motion <an undulating sea of grass>.

UNDULATE Defined for Kids


verb un·du·late \ˈən-jə-ˌlāt, -də-, -dyə-\

Definition of undulate for Students



  1. :  to move in or as if in a wavy or flowing way <The curtains were streamers, undulating from the breeze … — Gail Carson Levine, Ella Enchanted>

Word Root of undulate

The Latin word unda, meaning “wave,” gives us the root und. Words from the Latin unda have something to do with waves. To undulate is to move up and down like a wave. To inundate is to cover with a flood of waves. To surround, or encircle on all sides, is to enclose as if by waves. To abound is to be plentiful, like waves in the ocean.

Medical Dictionary


play play play
adjective un·du·late \ˈən-jə-lət, ˈən-d(y)ə-, -ˌlāt\

Medical Definition of undulate

  1. :  having a wavy surface, edge, or markings <an undulate cell>

Learn More about undulate

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different from the usual or normal

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