To live in someone's house and take care of it while they are away(verb)
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Use "house-sit" in a sentence
"We'd love to make contact with other expats in this area, and would appreciate referrals as to properties there that could be available to house-sit or rent during October/November."
"I go stay in my own house a day or so a week just to house-sit and do laundry."
"A month after moving, a local police officer whom they previously had house-sit their Mexican property was abducted and murdered, Reta says."