preteen

Noun
  1. A preadolescent boy or girl (usually between 9 and 12 years of age) (synset 109650451)
    "little league is intended for the preteens"
Adjective
  1. Of or relating to or designed for children between the ages of 9 and 12 (synset 301653713)
    "a preteen party"; "preteen clothing"

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