relative in law
/ˈrɛlətɪv ɪn ˌlɔ/
noun
- A person who is related to you by marriage, not by blood.
- My sister's husband is my brother-in-law, a type of relative-in-law.
- We invited all our relatives-in-law to the family reunion, including my wife's parents.
- After the wedding, I gained several new relatives-in-law, like my spouse's cousins.
Synonyms