Astute is an adjective used to describe someone who is clever, smart, or quick-witted. Synonyms for astute include shrewd, sharp, discerning, insightful, and perceptive. A shrewd person has a keen sense of judgment and is good at making practical decisions. Someone who is sharp is quick in understanding and mentally agile. A discerning individual has the ability to judge carefully and accurately. An insightful person is someone who has a deep understanding of people and situations. Finally, perceptive people are able to quickly grasp ideas, situations, and people's emotions or thoughts. All these synonyms emphasize an individual's ability to observe, understand, and make good judgments.