perspicacious (adj.)

• acute
• all-knowing
• apperceptive
• apprehensive
• astute
• aware
• cagey
• cogent
• cognizant
• comprehending
• conscious
• discerning
• farseeing
• farsighted
• foresighted
• forethoughtful
• heady
• incisive
• insightful
• intelligent
• judicious
• knowing
• knowledgeable
• longsighted
• mindful
• omniscient
• penetrating
• perceptive
• percipient
• perspicuous
• piercing
• prehensile
• provident
• sagacious
• sensible
• sharp-sighted
• shrewd
• trenchant
• understanding
• wise