noun, plural ju·ve·nil·i·ties.
- juvenile state, character, or manner.
- juvenilities, youthful qualities or acts.
- an instance of being juvenile.
noun plural -ties
- the quality or condition of being juvenile, esp of being immature
- (often plural) a juvenile act or manner
- juveniles collectively
1620s, from Latin iuvenilitas “youth,” from iuvenilis (see juvenile).