Small house is an informal term in Zimbabwe used to refer to the female partner in an extra-marital affair where the man is married. The term 'small house' implies that the man's marriage spouse is the main house. Some also use the term to refer to the actual house but this is rarely the case.
The term rose in popularity in the early 00s and is now a generally accepted term locally.
The term small house is strictly used for extramarital affairs and is never used to refer to female partners in formal polygamous marriages.
In popular culture
Small House Saga was the name of a TV series in Zimbabwe.