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general::
Phrase(s): Come in and sit a spell. [and] Come in and set a spell.; Come in and sit down.; Come in and take a load off your feet.
Rur. Please come in and have a seat and a visit. (The variant with set informal or folksy.) • "Hi, Fred," smiled Tom, "Come in and sit a spell." • Tom: I hope I’m not intruding. Bill: Not at all. Come in and set a spell.
McGrawhill's American Idioms And Phrasal Verbs