term:

Common-Law Marriage

common-law marriage n

: a marriage that is without a ceremony and is based on the parties' agreement to consider themselves married and usually also on their cohabitation for a period and their public recognition of the marriage compare concubinage NOTE: Most jurisdictions no longer allow this type of marriage to be formed, although they may recognize such marriages formed prior to a certain date or formed in a jurisdiction that does permit common-law marriages.

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.