The uncontrollable back and forth circular motions made by a woman's hips when her man has made her horny but is not there to satisfy her sexual cravings and NEEDS.
My hips undulate when I'm in the saddle, riding you.

My hips undulate wildly when you are far away and we have phone sex. That's phone fucking at it's best.

When you talk naughty to me like THAT, my ass take on a life of it's own, undulating relentlessly while your words make me cum over the phone. I quiver. I convulse, I spasm. I cum. Undulating ceases.
by zazz July 28, 2012
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moving from side-to-side or back and forth; rocking, basically the motion a female does when shes riding you
that boat undulates in the water

I like it when she straddles me and undulates
by suprmn90 June 2, 2010
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Verb. The act of urination.

Given because of the oscillating motion made by the penis upon the sucessful completion of a piss to dislodge any dewdrops.
The large phallus undulated a stream of hot liquid into her eyes.
by Beaver Muncher November 23, 2004
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You probably don't want to know, but it sounds like one of those words you learn in health class. Yeah.
Holy sh!t! How did that undulation end up on the wall!

We had to evacuate the pool because she undulated in it.
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Rob made her squel when he poked her with his undulating thrum bobber.
by Rob Wilkinson November 4, 2005
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Oh come here baby and let me fettle you undules....
by Nicky January 14, 2005
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