plâtre

plaster, plaster of Paris (the building material); plaster, cast (supportive and immobilising device)

Inherited from Middle French plâtre, plastre, from Old French plastre (first attested ca. 1165), from Vulgar Latin *plastrum (attested later in Medieval Latin plastrum), from Latin emplastrum, from Ancient Greek ἔμπλαστρον (émplastron, “daub; salve”). Doublet of piastre.