Adjective adjective: lenient 1. (of punishment or a person in authority) permissive, merciful, or tolerant. "judges were far too lenient with petty criminals" synonyms: merciful, clement, forgiving, forbearing, tolerant, charitable, humane, indulgent, easygoing, magnanimous, sympathetic, compassionate, mild "Brother Andrew was a lenient teacher" antonyms: severe 2. archaic emollient.