plainer

adj

1. (comparative, form-of)comparative form of plain: more plain

   “Of the two, she was certainly the plainer.”

noun

1. A policeman who wears plainclothes.

   “Three pandas were parked round the edge of the wee swing park, lights spinning, flashing blue on a huddle of plainers over by the iron roundabout.”

   “The plainer, he was from the Marine police station on Anderson Street and Davin or Devine or something was his name — said nothing.”

   “A guy and a girl make ideal plainers; nobody gives them a second thought; people just assume they're a couple.”