schoolgirlish

/ˈskulˌɡɜrlɪʃ/
adjective
  1. Characteristic of or typical of a schoolgirl, especially in being innocent, shy, or overly enthusiastic.
    • He gave her a schoolgirlish grin when she complimented him.
    • Her schoolgirlish excitement about the trip was contagious.
    • The movie had a schoolgirlish charm that appealed to younger audiences.
Antonyms
What does "schoolgirlish" mean? | whatsthatwordmean | whatsthatwordmean