The Collaborative International Dictionary of English v.0.48:
incisiveness \incisiveness\ n. keenness and forcefulnelss of thought or expression or intellect. Syn: trenchancy. [WordNet 1.5]WordNet (r) 3.0 (2006):
incisiveness n 1: keenness and forcefulness of thought or expression or intellect [syn: incisiveness, trenchancy]