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Poultice made of mustard.

A cataplasm, of which mustard forms the basis, which is used for exciting redness, and acting as a counter-irritant. It is prepared by mixing flour of mustard and vinegar together to the due consistence. See Cataplasma sinapis.

A mustard-plaster or paste.

A mustard plaster or poultice. [Lat.]

n. [Greek] Mustard seed pulverized with Borne other ingredients, used as an external application.