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Synonyms for Lethargy (same or very similar meaning)

WordNet sense 1 (a state of comatose torpor (as found in sleeping sickness)):
lassitude, sluggishness

WordNet sense 2 (weakness characterized by a lack of vitality or energy):
inanition, slackness

WordNet sense 3 (inactivity; showing an unusual lack of energy):
flatness, languor, phlegm


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