What is "setting coat"

Setting \Set"ting\, n.

1. The act of one who, or that which, sets; as, the setting of type, or of gems; the setting of the sun; the setting (hardening) of moist plaster of Paris; the setting (set) of a current.

2. The act of marking the position of game, as a setter does; also, hunting with a setter.
   --Boyle.

3. Something set in, or inserted.

   Thou shalt set in it settings of stones.
   --Ex. xxviii. 17.

4. That in which something, as a gem, is set; as, the gold setting of a jeweled pin.

5. the time, place, and circumstances in which an event (real or fictional) occurs; as, the setting of a novel.

   Setting coat (Arch.), the finishing or last coat of plastering on walls or ceilings.

   Setting dog, a setter. See Setter, n., 2.

   Setting pole, a pole, often iron-pointed, used for pushing boats along in shallow water.

   Setting rule. (Print.) A composing rule.

n. The finishing or last coat of plastering on walls or ceilings.