A young male.
(diminutive) A male child: a son of any age.
(diminutive) A male of any age, particularly one rather younger than the speaker.
A male of low station, (especially as pejorative) a worthless male, a wretch; a mean and dishonest male, a knave.
(now rare and usually offensive outside some Commonwealth nations) A male servant, slave, assistant, or employee, particularly:
Any non-white male, regardless of age.
A male animal, especially, in affectionate address, a male dog.
A former low rank of various armed services; a holder of this rank.
Heroin.
(somewhat childish) A male (tree, gene, etc).
To use the word “boy” to refer to someone.
To act as a boy (in allusion to the former practice of boys acting women's parts on the stage).
Exclamation of surprise, pleasure or longing.