noun
single-person household
A household consisting of one person living alone. Often used in official statistics and demographic contexts.
日本では単身世帯が増えている。
Single-person households are increasing in Japan.
一人暮らし is a more everyday term for living alone, while 単身世帯 is a formal, statistical term for a single-person household.
Compound of 単身 (single person) and 世帯 (household).