Slack meaning: If you slow down at

If you slow down at the end of a race, you slack off. When you use slack this way, it means to reduce your speed, to be sluggish, or to be negligent. Slack definition: not tight, taut, firm, or tense;. See examples of SLACK used in a sentence. SLACK meaning: 1. not tight; loose: 2. showing little activity; not busy or happening in a positive way: 3. the…. Learn more. Slack can be an adjective, verb, noun, or adverb with different meanings related to looseness, negligence, or dullness. Learn how to use slack in various contexts and see synonyms, pronunciation, and examples.