married person; householder
Refers to a person who is married and maintains a household. Often used in contexts discussing responsibilities, lifestyle, or social status of married individuals.
He's a married man with a household, so he can't just quit his job.
Once you become a householder, your free time decreases.
世帯主 is the official head of a household, often used in administrative contexts. 所帯持ち is a more colloquial term for a married person with household duties.
Compound of 所帯 (しょたい, 'household') and 持ち (もち, 'holder'). The exact historical derivation is uncertain, but the term naturally describes someone who maintains a household.