It is an adjective.
Meaning : insightful.It indicates the keen perception and understanding of a person or a subject.
Root of the word : spec/spic/spect which means look, see
perspicaciously - adverb
perspicaciousness - noun
Antonyms: inattentive, dull,stupid
1)It is astonishing that a perspicacious person like John did not spot the blunder in the computer program.
2)Today's scenario demands for a perspicacious leadership.
3)It is much too perspicacious that he is trying to provoke me into the argument.