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Webster 1913 Edition

(kăn-thăr′ĭ-dĭn)

Noun.

(Chem.)

The active principle of the cantharis, or Spanish fly, a volatile, acrid, bitter solid, crystallizing in four-sided prisms.

Noun.

That peculiar substance existing in the Meloe vesicatorius, or cantharides, which causes vesication.

cantharidin ‎(plural cantharidins)