n.: subtlety, shrewdness, ability to understand and judge things quickly and clearly, perceptive, have a thin skin, have a thick skin, keen, acuity, subtleties, sagacity, perspicacity, penetration, keenness, delicacy, bezazz, acute, acumen
adj.: sharp, quick
French Expression
adj. vif, fin
Thesaurus
astuteness, acumen, bear a brain, adept, definitude of verdict, sagaciousness, elaborate, art, address, cunning, fineness