DictionarylethargyLack of energy
noun

lethargy

LETH-er-jee/ˈleθərdʒi/

A state of tiredness and sluggishness.

The woman's lethargy leaves her slumped over an untouched breakfast.

An older woman sits heavily slumped at a small breakfast table, barely supporting her drooping head, with half-open eyes and a limp arm beside an untouched meal.
Etymology

Greek lēthargia meant “forgetfulness.” In English, the word denoted prolonged torpor or inactivity of body or mind, providing the bridge to its current sense of extreme tiredness or lack of energy.

In context

Enhanced Public Domain306:23
a violent fever intervened which the Physicians did all in their power to allay as soon as his reason returned a little Alexander aroused himself from his lethargy
Alexander the Great Biography (Audiobook)

More examples

  • The summer heat brings on a wave of lethargy.
  • Her usual energy returns as the lethargy fades.
  • Persistent lethargy can make even simple chores feel difficult.

Forms

lethargy

lethargic adjective — Feeling tired, sluggish, and lacking energy.

lethargically adverb — In a slow manner lacking energy.

Similar words

fatigue
Emphasizes tiredness rather than sluggish movement or reduced activity.
sluggishness
Emphasizes slow movement or response, not necessarily feeling tired.