Definition of lethargic in US English:



  • Affected by lethargy; sluggish and apathetic.

    ‘I felt tired and a little lethargic’
    • ‘After seemingly endless weeks of constant commotion, they appear listless and lethargic.’
    • ‘As a result, many seemed lethargic and sluggish when it came to taking the game to Brazil in the second half.’
    • ‘I breeze through the Pilates class, where everybody else was tired and lethargic.’
    • ‘Is he shaking with rigors, is he awake and alert and comfortable, or is he lethargic?’
    • ‘If you are confused, lethargic, or have a fever, someone should take you to the hospital.’
    • ‘If we are too relaxed, we become lethargic, wasteful and languid.’
    • ‘Mrs Lewis said she had felt unwell, lethargic, irritable and overweight for many years.’
    • ‘The boy was lethargic and confused but seemed to recognise his mother.’
    • ‘While such a form of epilepsy would not feature seizures, the condition can be seen in lethargic children.’
    • ‘Over the previous two days he had been feeling increasingly tired, lethargic, polyuric, and thirsty.’
    • ‘However, presentations where a patient is hypo-alert and lethargic may go unrecognised.’
    • ‘I got very sick and I had inflammation of the brain, and I was very lethargic.’
    • ‘If the cat is lethargic and his coat is dull and unhealthy looking, this too may be a sign.’
    • ‘He had pneumonia and diarrhoea and was severely anaemic and lethargic.’
    • ‘All of us were suffering from headaches, feeling nauseated and very lethargic.’
    • ‘Most claimed to be fully adherent only on occasions when they felt lethargic or unwell.’
    • ‘Its rulers could not have been that lethargic, or its diplomacy so tortuous, for it to have survived for such a long period.’
    • ‘Her health was poor, although stable, until the morning of admission, when she became disoriented and lethargic.’
    • ‘Furthermore, filling up on fatty foods like bacon or cheese makes you tired, lethargic and apathetic.’
    • ‘They looked tired and lethargic with absolutely none of the sparkle we have associated with them in the past.’
    sluggish, inert, inactive, slow, torpid, lifeless, dull
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Late Middle English: via Latin from Greek lēthargikos, from lēthargos ‘forgetful’.