What does mate mean?
“Mate” is a versatile word for a companion, partner, friend, or breeding partner, as well as a verb meaning to reproduce sexually or to breed animals. In informal British and Australian English, it is often used to address a friend, though the familiarity implied by the term can be inappropriate in formal or sensitive situations. In relationships and animal breeding, it identifies the other participant in a pairing. In chess, “mate” refers to the final move of a sequence that leaves the opposing king in check with no legal escape. The word can sound warm and sociable in casual conversation, but its more literal uses are practical and matter-of-fact. It is especially useful in discussions of companionship, animal breeding, and chess, where it describes a clear pairing or concluding move.
A companion, friend, partner, or sexual partner; also, an animal’s breeding partner or a shipboard officer addressed by a familiar title.
"The two dogs are a suitable mate pair."
The informal sense for a friend is especially common in British and Australian English. The romantic or sexual sense is neutral, while the animal-breeding sense is technical or practical.
To have sexual intercourse or to breed animals; in chess, to place the opponent’s king in a position from which it cannot escape capture.
"The farmer waits for the cows to mate before moving them to another field."
The verb is neutral or technical in animal-breeding contexts and less common in formal sexual-health contexts. In chess, it names the concluding capture of the king.
Countable when referring to companions, partners, animal breeding partners, or the shipboard officers; usually plural in the informal sense of friends.
"They are good mates and often travel together."
The word “mate” means both a close companion and the act of reproducing—an unusually compact example of how English links human relationships with animal breeding.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does mate come from?
The word has several overlapping historical paths. Its familiar use as an informal form of address developed in the early modern period, while the older noun sense for a companion or partner and the verb sense relating to breeding come from established English usage. The separate chess sense developed through the game’s tradition of describing a decisive final move as “mate.”
Related word forms
How mate is actually used
As a term for a friend, “mate” is common in informal British and Australian English and can sound familiar, casual, or mildly patronizing depending on tone. As a noun for a romantic or sexual partner, it is neutral and sometimes clinical. “Mate” is also the standard term in animal breeding.