man who marries into his wife's family; adopted son-in-law
Refers to a man who takes his wife's family name and becomes a member of her household, often in a traditional family succession context.
He entered his wife's family as an adopted son-in-law.
The custom of the adopted son-in-law has existed since old times to carry on the family line.
婿養子 is a more formal legal term for a son-in-law who is adopted as a son, while 入り婿 is a common noun describing the man and his role.
嫁入り refers to a woman marrying into her husband's family, the opposite direction of 入り婿.
Standard kanji spelling.
Variant without okurigana; less common but still used.
Rare variant using 聟 (a variant of 婿).
Rare variant using 壻 (an older variant of 婿).
Compound of 入り (iri, 'entering') + 婿 (muko, 'son-in-law'). The exact historical derivation is uncertain, but the word has been used to describe a man who marries into his wife's family.