n A man of any age, used as a friendly diminutive, or of a man who is merely younger than the speaker. (defdate|from 17th c.)
n (colloquial) A male friend or fellow of some group, community etc. (mainly used in the plural). (defdate|from 19th c.)
v (transitive) To act as a boy (in allusion to the former practice of boys acting women's parts on the stage).