backstairs
1. [ adjective ] secret and sly or sordid
Synonyms: furtive backstair
Examples:

"backstairs gossip" "his low backstairs cunning"- A.L.Guerard "backstairs intimacies" "furtive behavior"

Related terms: covert
2. [ noun ] (architecture) a second staircase at the rear of a building
Related terms: stairway
Similar spelling:   backstair
  backstroker
  backscatter
  basketeer
  backtrack
  Backstrom
  backstroke