1 definition by Midnight Ghost Writer

A method of conception, impregnation, or insemination in which a man's penis is sexually stimulated by blowjob, handjob, etc. and immediately inserted into the vagina prior to orgasm and ejaculation thus creating a creampie.

Named after a certain idiot named Glen.

An antonym of onanism.
He did an unprotected glenism last night — what an idiot!
by Midnight Ghost Writer October 17, 2014
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