slack noun verb adjective Stress: first syllable 🤍 Save Syllables: slack (1) English Definition Not taut or held tightly; loose. Example Sentence The rope was very slack. US IPA /slæk/ 🔊 Listen US UK IPA /slæk/ 🔊 Listen UK Synonyms loose lax limp sluggish Antonyms tight taut busy Share this Word Facebook WhatsApp X Telegram Copy Link