What is having nice discernment; perceiving or using minute distinctions; penetrating; clever; shrewd; -- opposed to Ant: dull or Ant: stupid; as, an acute observer; acute remarks, or reasoning called?

acute — Having nice discernment; perceiving or using minute distinctions; penetrating; clever; shrewd; -- opposed to Ant: dull or Ant: stupid; as, an acute observer; acute remarks, or reasoning. (Webster's 1913.)

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