godan verb (-u), intransitive verb
pair up; form a pair; become paired
Intransitive; describes two things or people naturally coming together as a pair, often used for birds, objects, or abstract pairings.
See also: 番い
この鳥は一生同じ相手とつがう。
This bird pairs up with the same partner for life.
The socks don't pair up properly.
godan verb (-u), intransitive verb
Used for animals; neutral biological term. Not used for humans in polite contexts.
春になると、多くの動物がつがう。
In spring, many animals mate.
godan verb (-u), transitive verb
fix an arrow to the string; place outriders; make a firm promise
Archaic transitive uses. Sense 3: nock an arrow. Sense 4: historical military term for positioning outriders. Sense 5: old expression for making a solemn promise. All are obsolete in modern Japanese.
See also: 番える
古文書では、矢をつがう動作を「番う」と記すことがある。
In old documents, the act of nocking an arrow is sometimes written as 番う.