Define exactly . exactly synonyms, exactly pronunciation, exactly translation, English dictionary definition of exactly . adv. 1. In an exact manner; accurately. 2. In all respects; just: Do exactly as you please. 3. As you say. Used to indicate agreement. American Heritage®... Exactly definition: in an exact manner; precisely; accurately.. See examples of EXACTLY used in a sentence. exactly (comparative more exactly , superlative most exactly ) (manner) Without approximation; precisely. quotations Measure exactly so we can be sure it is right. The edge is not exactly straight. He divided the coins exactly in half. This comprehensive entry on " exactly " delves into its precise meaning, detailed etymology, and varied real-world applications. Enhance your vocabulary with definitions, synonyms, and practical examples for this essential adverb.