1.
mother-in-law
One's spouse's mother.
2.
stepmother
A woman married to one's father who is not one's biological mother.
Terms of address
While 義母 is the formal/written term, in conversation people typically address their mother-in-law as:
- お義母さん - most common (same pronunciation as the ordinary word for "mother")
- 義理のお母さん - explicit "in-law's mother"
Usage
義母 is more commonly used in:
- Written documents
- Speaking about (not to) one's mother-in-law
- Formal contexts
The ぎ- prefix indicates a family relationship through marriage rather than blood.
FAMILY TERMS WITH THE ぎ- PREFIX:
Related Words
Related:
義父 (father-in-law)
Compare:
母 (mother (biological))
Related:
舅 (father-in-law)
Related:
義兄 (brother-in-law (older))