lethargic

luh-THAR-jik /lɪˈθɑːdʒɪk/
adjectiveB2GRESATTOEFLIELTS
generalmedical

Affected by deep tiredness, abnormal drowsiness, or lack of energy.

Describes a physical or physiological state of severe exhaustion or heavy sluggishness.

The story behind the word. In Greek mythology, souls drinking from the River Lethe forgot their earthly existence. The Greeks combined 'lēthē' (forgetfulness) and 'argos' (idle) to coin 'lethargos,' describing a state of heavy, forgetful drowsiness.

Word relationships

  • apathetic: Apathetic means lacking emotional interest or care, whereas lethargic means lacking physical vitality.
  • fatigued: Fatigued means weary from exertion, while lethargic emphasizes heavy, slow indifference in physical movement.
  • animated: Animated means full of life, spirit, and active energy.
  • energetic: Energetic indicates high physical endurance and activity.

Commonly confused with

  • apathy: Apathy is a lack of emotion or caring; lethargy is a lack of physical energy.

Word family

  • lethargy (noun): A state of tiredness, abnormal drowsiness, or lack of energy.
  • lethargically (adverb): In a drowsy or unenergetic manner.

Collocations

  • feel lethargic
  • lethargic state
  • lethargic response

Idioms & expressions

  • running on empty
  • out of steam

Example sentences

  • "The patient felt unusually lethargic for several days following the viral infection." Medical observation
  • "A hot, humid afternoon in July always leaves me feeling lethargic." Daily life

Memory hook

LETHARGIC: Drinking from the river LETHE makes you forgetful and slow. Drunk on Lethe's water.

When not to use

Do not use to describe a conscious refusal to work; it is an involuntary loss of physical energy.

Fun facts

  • In ancient Greek medical theories, lethargy was considered a physical illness caused by an excess of phlegm.

Related words

sluggish, languid

Explore more words

apathetic, slouch, lugubrious

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