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husband; groom
(one's) son-in-law
娘の聟となる青年に初めて会う日が来た。
The day came to meet the young man who would become my daughter's husband.
聟に家業を継がせる計画を立てている。
I am making plans to have my son-in-law take over the family business.
聟として婿入りした彼は家族にすぐ馴染んだ。
He married into the family and quickly fit in.