tweenage
Not yet a teenager, but starting to act like oneNot yet a teenager (being less than thirteen years old), but starting to act like one.
Dictionary text adapted from Wiktionary (Wiktionary contributors, CC BY-SA 4.0) and Open English WordNet / Princeton WordNet (CC BY 4.0, WordNet License); shared under CC BY-SA 4.0. Example sentences and recordings are credited where they appear.