intelligent

modif.

1. Said of persons or beings

   clever, bright, astute, acute, smart, brilliant, perceptive, well-informed, resourceful, profound, penetrating, original, exceptional, perspicacious, keen, imaginative, inventive, reasonable, capable, able, precocious, gifted, ingenious, knowledgeable, creative, alive, responsible, understanding, alert, quick-witted, keen-witted, clearheaded, quick, sharp, witty, ready, calculating, rational, thoughtful, comprehending, listening to reason, discerning, having one's wits about one, having it in one, discriminating, knowing, intellectual, on the qui vive, sagacious, studious, contemplative, having a head on one's shoulders, talented, apt, deep, sage, wise, shrewd, brainy*, smart as a whip*, all there*, on the ball*, on the beam*, not born yesterday*, nobody's fool*, crazy like a fox*; see also clever 1, judicious.

   Antonyms dull*, slow-witted*, stupid. *

2. Said of conduct

   sensible, farsighted, rational; see sense 1; judicious.

intelligent implies the ability to learn or understand from experience or to respond successfully to a new experience; clever implies quickness in learning or understanding, but sometimes connotes a lack of thoroughness or depth; alert emphasizes quickness in sizing up a situation; bright and smart are somewhat informal, less precise equivalents for any of the preceding; brilliant implies an unusually high degree of intelligence; intellectual suggests keen intelligence coupled with interest and ability in the more advanced fields of knowledge