common-law marriage(n = noun.state) - a marriage relationship created by agreement and cohabitation rather than by ceremony;
is a kind of marriage, matrimony, spousal relationship, union, wedlock

civil marriage, common-law, dissolution of marriage, marriage, marriage bed, marriage broker, marriage brokerage, marriage ceremony, marriage contract, marriage counseling, marriage licence, marriage license, marriage mart, marriage of convenience, marriage offer, marriage proposal, marriage settlement, mixed marriage, open marriage, outside marriage, proposal of marriage, same-sex marriage