Acuminate

v. t. To render sharp or keen. [Rare.] “To acuminate despair.” Cowper.

v. i. To end in, or come to, a sharp point. “Acuminating in a cone of prelacy.” Milton.

a. [Lat. acuminatus, p. p. of acuminare; from acumen, q. v.] (Bot.) Having a long, projecting, and highly tapering point. Gray.