backstairs

plural noun

Stairs at the back or side of a building.

adjective

Underhanded or clandestine.

SYNONYMS

below the beltcheatingdeceitfuldirtydishonestdishonourabledisreputabledouble-dealingdubiousduplicitousfraudulentimmoralJanus-facedtreacheroustwo-facedtwo-timingunderhandedunethicalunfairunprincipledunscrupulousunsportingunsportsmanlike