9 letters · 15 points in Scrabble
adjective deficient in alertness or activity
originLearned borrowing from Ancient Greek ληθαργικός (lēthargikós), from λήθαργος (lḗthargos, “forgetful, lethargic”), from λήθη (lḗthē, “a forgetting, forgetfulness”) (from which Lethe (“river in Hades”)) + ἀργός (argós, “not working”). By surface analysis, lethargy + -ic.
Etymology from Wiktionary, CC BY-SA 3.0