いっぱし

noun which may take the genitive case particle 'no', adverb

fully fledged; competent; proper

Describes someone or something that has reached a respectable, full-fledged level, often with a nuance of 'in one's own right' or 'as much as anyone else'. Used adverbially or with の.

• 彼かれもいっぱしの大人おとなになった。

  He has become a fully fledged adult, too.

• いっぱしの口くちをきくようになったね。

  You've started talking like a proper grown-up, haven't you?