A way of saying a man got a boner, stiffy, erection, etc.

Sized up is a play on the phrase 'siezed up'.
Alexa: I came twice in a row thinking about last night

Jordan: Dayumm I just sized up hard
by Alexob April 6, 2014
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when you look at someone’s thighs to see how far your 🍆 will fit inside them.
“dude, i sized up my girl the other day. that sh¡t would fit all the way
by arf arf arf July 23, 2021
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The act of checking someone out to see if you can take them in a fight
Chad told me he was sizing up brad and he thinks he can take him.
by DomToretto July 18, 2021
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He did size up the potential destruction, but did not act decisively in the end.
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The phrase "size up", usually used in arguments, essentially means to "stand up and fight"
"Yo, no long talkin' b. Either size up or nize up"

In other words...

"Hey man, I don't want to do this long talking business anymore. Either stand up to me and let's fight, or shut up."
by suwayy March 15, 2017
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The act of looking at someone and determining if you could take them in a fight.
Conor was sizing up Jake for their big fight and thinks he can win.
by LordFarquadd July 25, 2021
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To get a feel of someone's strength by observing them or a call out to get someone to fight you

This pretty simple term which was then redefined by tiktok idiots into: When a man looks if his dick will fit by checking out a girl's thighs.
Bro 1: Bro, I fucked your mom

Bro 2: Size up, bitch.

Bro 1: Bet

What tiktok idiots think it is:

Girl: OMG you're so gross, why are you sizing me up?

Boy: Umm... I wasn't. I don't want to fight
by NNatty August 14, 2021
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