verb (used without object), house·sat, house·sit·ting.
to take care of a house or residence while the owner or occupant is temporarily away, especially by living in it.
Origin of housesit
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
verb -sits, -sitting or -sat (intr)
to live in and look after a house during the absence of its owner or owners
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012