noun
married person
Neutral term for a person who is married. Often used in contrast with 未婚者 (unmarried person).
彼は既婚者ですが、子供はいません。
He is a married person, but he has no children.
このイベントは既婚者限定です。
This event is limited to married people.
独身 is a more common, everyday word for 'single' or 'unmarried', while 既婚者 is a formal, categorical term.
Compound of 既婚 (kikon, 'already married') + 者 (sha, 'person').