incisive (adj.)

early 15c., inscisif, "slashing, cutting with a sharp edge," from Old French incisif (medical) "invasive, effective," and directly from Medieval Latin incisivus, from Latin incis-, past participle stem of incidere "to cut into" (see incision). Originally literal; figurative sense of "mentally acute, sharply and clearly expressive" first recorded 1850 as a borrowing from French. Related: Incisively; incisiveness.