Emily Dickinson Lexicon

PU-ER-IL'I-TY, or PU'ER-ILE-NESS, n. [Fr. puerilité; L. puerilitas, from puer, a boy.]

1. Childishness; boyishness; the manners or actions of a boy; that which is trifling. – Brown. Dryden.
2. In discourse, a thought or expression which is flat, insipid or childish. – Encyc.