This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. To cause to move in a smooth wavelike motion.

v. To give a wavelike appearance or form to.

verb-intransitive. To move in waves or with a smooth, wavelike motion. See Synonyms at swing.

verb-intransitive. To have a wavelike appearance or form.

verb-intransitive. To increase and decrease in volume or pitch as if in waves.

adj. Having a wavy outline or appearance: leaves with undulate margins.

v. To cause to move in a wavelike motion.

v. To cause to resemble a wave

v. To move in wavelike motions.

v. To appear wavelike.

adj. Wavy in appearance or form.

adj. Changing the pitch and volume of one's voice.

adj. Winding up and down gradually relative to the blade.

adj. Same as undulated.

v. To cause to move backward and forward, or up and down, in undulations or waves; to cause to vibrate.

verb-intransitive. To move in, or have, undulations or waves; to vibrate; to wave.

Wavy; having a waved surface.

To have a wavy motion; rise and fall in waves; move in waves.

Synonyms Waver, etc. See fluctuate.

To cause to wave, or move in waves; cause to vibrate.

adj. having a wavy margin and rippled surface

v. stir up (water) so as to form ripples

v. move in a wavy pattern or with a rising and falling motion

v. occur in soft rounded shapes

v. increase and decrease in volume or pitch, as if in waves

"With the precision placement of bricks made possible by a robot, it ought to be possible to build a flat wall that would undulate in 3D when viewed as a stereogram."

smooth   

undulated    undulates    undulating   

flux    flow    change   

swing    billow   

undulated   

undulated    undulating   

vibrate    wave    agitate    crinkle    ripple    roll   

grassy    hilly    uneven    verdant    fertile    moonlit    swampy    lush    unbroken    sinuous