Simply, squishy cheeks on ones face. It can be made by fat, but it is not limited to this - things like jaw alignment or soft/flexible skin can result in poonum.

When someone has a lot of poonum, it is very amusing to poke this person's cheek with a your finger and say poonum in a childish voice.
"Dude! Look at T-Dawg's cheeks. *pokes cheek* Heh heh, poonum!"
by Ramous July 3, 2006
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A word used to describe a enormously gay person or a sick, loose, floppy vag.
1. Dude, that guys is the biggest poonum fuck ive ever seen

2. She has the floppiest poonum ive ever fucked
by Poonum April 20, 2005
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Someone who loves the online game of Runescape
Yo what you get up to last night?
I was online gaming being a right Poonum
by Epicyorkie February 9, 2021
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