\Plas"ter\, n. [AS., a plaster (in sense 1), fr. L.
emplastrum, Gr. ?, ?, fr. ? to daub on, stuff in; ? in + ? to
mold: cf. OF. plastre a plaster (in sense 2), F. pl[^a]tre.
Cf. {Plastic}, {Emplaster}, {Piaster}.] [Formerly written
also {plaister}.]
1. (Med.) An external application of a consistency harder
   than ointment, prepared for use by spreading it on linen,
   leather, silk, or other material. It is adhesive at the
   ordinary temperature of the body, and is used, according
   to its composition, to produce a medicinal effect, to bind
   parts together, etc.; as, a porous plaster; sticking
   plaster.
2. A composition of lime, water, and sand, with or without
   hair as a bond, for coating walls, ceilings, and
   partitions of houses. See {Mortar}.
3. Calcined gypsum, or plaster of Paris, especially when
   ground, as used for making ornaments, figures, moldings,
   etc.; or calcined gypsum used as a fertilizer.
{Plaster cast}, a copy of an object obtained by pouring
   plaster of Paris mixed with water into a mold.
{Plaster of Paris}. [So called because originally brought
   from a suburb of Paris.] (Chem.) Anhydrous calcium
   sulphate, or calcined gypsum, which forms with water a
   paste which soon sets or hardens, and is used for casts,
   moldings, etc. The term is loosely applied to any plaster
   stone or species of gypsum.
{Plaster of Paris bandage} (Surg.), a bandage saturated with
   a paste of plaster of Paris, which on drying forms a
   perfectly fitting splint.
{Plaster stone}, any species of gypsum. See {Gypsum}.

\Plas"ter\, v. t. [imp. & p. p. {Plastered}; p. pr. &
vb. n. {Plastering}.] [Cf. OF. plastrer to plaster (in sense
2), F. pl[^a]trer.]
1. To cover with a plaster, as a wound or sore.
2. To overlay or cover with plaster, as the ceilings and
   walls of a house.
3. Fig.: To smooth over; to cover or conceal the defects of;
   to hide, as with a covering of plaster. --Bale.