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adj. Of, relating to, or characteristic of prepuberty.

n. A prepubescent child.

adj. Before the age at which a person is first capable of sexual reproduction.

adj. Who is not yet capable of sexual reproduction. Immature.

Prior to the occurrence of puberty.

adj. (especially of human beings) at the age immediately before puberty; often marked by accelerated growth

"A few examples: I was pretty stoked when Ugly Betty‘s Henry and Betty separated — a zit-plagued prepubescent is less awkward than that relationship — and didn’t really bat an eyelash when Jack and Kate ended their relationship on Lost."

immature   

postpubescent    pubescent    puberty   

found    two-grown    uncertain    formed    called