Meaning of “lethargic” - Learner’s Dictionary

lethargic

adjective uk us /ləˈθɑːdʒɪk/

having no energy and not wanting to do anything

lethargy uk us /ˈleθədʒi/ noun [ U ]

the feeling of being tired and having no energy

(Definition of “lethargic” from the Cambridge Learner’s Dictionary © Cambridge University Press)