In-cī'sive, a.

a. [Lat. incisivus, It. & Sp. incisivo, Pr. incisiu, Fr. incisif.] Having the quality of incising, cutting, or penetrating, as with a sharp instrument; cutting; hence, sharp; acute; sarcastic; biting.

And her incisive smile accrediting That treason of false witness in my blush. Browning.

Incisive bones (Anat.), the bones of the upper jaw, which contain the incisors; the premaxillary bones. See SKULL.—Incisive teeth, fore teeth, the cutters or incisors.