'in-law' definitions:
Definition of 'in-law'
From: WordNet
noun
A relative by marriage [syn: in-law, relative-in-law]
Definition of 'in-law'
From: GCIDE
- in-law \in"-law`\, n. A person who is related by marriage, as distinguished from a blood relative; esp. mother-in-law (the mother of one's spouse), father-in-law (the father of one's spouse), brother-in-law (the brother of one's spouse, or husband of one's spouse's sister), sister-in-law (the sister of one's spouse, or wife of one's spouse's brother). [PJC]