apt brainy bright brilliant clever fast intelligent keen nimble quick sharp smart witty astute shrewd perceptive acute intellectual canny scholarly discerning erudite savvy alert genius cerebral wise perspicacious academic penetrating gifted bookish exceptional knowing studious observant able sapient cultured highbrow sensible knowledgeable prudent sage rational judicious sagacious cognizant insightful ingenious practical learned logical educated sound resourceful percipient understanding lettered literate schooled precocious considered genial practicable appropriate possible feasible workable heady valid accelerated balanced sane active light clear polymath polymathic trained informed crafty intuitive incisive politic calculating witting aware attentive reasonable responsible sly wily thinking streetwise artful cunning farsighted