Commonlaw husband is a term used to refer to a man who lives with a woman and assumes the role of her husband, without actually being legally married. However, there are several synonyms for the term, such as: 1. Partner: A partner refers to an individual with whom someone shares an intimate relationship, even though they may not be married. 2. Significant other: This term refers to a person who is important and influential in someone's life and is often used interchangeably with partner. 3. Cohabitant: A cohabitant refers to someone who lives with another person, often in a romantic or intimate relationship. 4. Domestic partner: This term is often used to describe an unmarried partner in a committed relationship. 5. Boyfriend: Although often used to describe less serious relationships, boyfriend can be used to describe a male partner in a serious, long-term relationship.