Translation guide
The English word 'mate' can refer to a friend, a romantic partner, an animal's partner, or a crew member. This guide covers natural Japanese expressions for each meaning, from casual friendship to formal relationships.
Referring to a close friend or companion in informal contexts.
Standard word for 'friend'. Neutral and widely used.
彼は私の一番の友達です。
He is my best mate.
Comrade, companion, or member of one's group. Implies shared activity or belonging.
彼は釣りの仲間だ。
He's my fishing mate.
Slang abbreviation of 友達 (ともだち). Very casual, used mainly by young men.
あいつは俺のダチだ。
That guy's my mate.
Referring to a spouse, boyfriend/girlfriend, or long-term romantic partner.
Formal term for spouse or life partner. Used in official contexts.
配偶者を同伴してください。
Please bring your mate.
Loanword for 'partner', commonly used for romantic or life partners, including same-sex relationships.
Boyfriend/girlfriend or sweetheart. Romantic but less formal than spouse.
Referring to an animal's sexual partner, especially in breeding contexts.
A pair of animals, especially birds, that mate. Can refer to the partner itself.
この鳥はつがいを見つけた。
This bird found a mate.
Literal 'mating partner'. Technical and biological.
オスは交尾相手を探している。
The male is looking for a mate.
Referring to a fellow worker on a ship or boat.
Crew member or sailor. General term for someone working on a ship.
彼は私の船員仲間です。
He is my shipmate.
Crew member, more formal and used for any vehicle (ship, plane, etc.).
In English, 'mate' is a very common casual term for friend, but Japanese has no exact equivalent. Using 友達 (ともだち) is safe, but overusing casual slang like ダチ can sound unnatural or overly masculine. In many contexts, simply using the person's name or a title is more natural than a generic 'mate'.
He is my life mate.
彼女は私の恋人です。
She is my mate.
乗組員は全員無事だった。
All the mates were safe.