What is Half-chub?
1.
An inkling of an erection. 1/2 a chubby, therefore 1/4 a full erection.
When I'm in the same room as hott chixxx, I get a half-chub.
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2.
A half erect penis, either a result of being only partialy aroused, or being paranoid of being caught.
"So then she took off her pants and was about to start riding me, but then Steve came home, and we had to stop all of a sudden. After he left, we tried to get back into it, but my wang was freaked out, and I couldn't get it up past half-chub, so we just gave up."
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3.
since a chub is a full erection that is thick in girdth, but not proportionate in length; a "half chub" describes anything between flacid and an all out boner.
damn reg! that girl is fine.... i'm gettin a half-chub just lookin at her.
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