Definition of plaster

• n. - 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.
• n. - A composition of lime, water, and sand, with or without hair as a bond, for coating walls, ceilings, and partitions of houses. See Mortar.
• n. - Calcined gypsum, or plaster of Paris, especially when ground, as used for making ornaments, figures, moldings, etc.; or calcined gypsum used as a fertilizer.
• v. t. - To cover with a plaster, as a wound or sore.
• v. t. - To overlay or cover with plaster, as the ceilings and walls of a house.
• v. t. - Fig.: To smooth over; to cover or conceal the defects of; to hide, as with a covering of plaster.