all the people who live together in one house [= house]: A growing number of households have at least one computer.
Families are classified by the occupation of the head of the household (=the person who earns the most money and is most respected in a house).
household - Definition from Longman English Dictionary Online
all the people who live in a house [= household]: He gets up at six and disturbs the whole house.
house - Definition from Longman English Dictionary Online
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