What is Onesie?
1.
A trademark registered to Gerber Childrenswear LLC, often used in connection with a one-piece garment for an infant or small child, generally worn over a diaper.
The child wore a Gerber Onesies garment.
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2.
A self rolled
Dave: Is there any weed left?
John: Nah man, not even enough for a onesie.
Dave: :(
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3.
to masturbate, have sex with oneself, to commit onanism
...and I caught that bitch having a onesie in the middle of the tennis court.
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