(informal) A young person belonging to a current popular fad or fashion subgenre, often relating to a musical genre.

(informal) A schoolchild who carries keys to his or her house because there is usually no parent home when school finishes.

(originally US, informal) A young adult who has moved back into the parental home after a period of independence.

(speech act, idiomatic) Used to attempt to make a serious point in a jocular conversation.

Alternative spelling of whiz kid

Alternative spelling of whiz kid

(informal) Synonym of younger sister

plural of kid sister

(informal) A little brother.

plural of kid brother