lethargic

adj.

Of, causing, or characterized by lethargy.

lethargically le·thar'gi·cal·ly adv.

adjective

1. Lacking mental and physical alertness and activity: hebetudinous, sluggish, stupid, stuporous, torpid. Slang dopey. See action/inaction.
2. Without emotion or interest: apathetic, detached, impassive, incurious, indifferent, insensible, listless, phlegmatic, stolid, unconcerned, uninterested, unresponsive. See feelings.

adj

Definition: lazy, sluggish
Antonyms: active, busy, energetic, lively, vigorous, vital, vivacious

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IN BRIEF: Abnormally drowsy. Also: Being slow or lazy.

I felt so lethargic after a full day in the hot sun.

Note: click on a word meaning below to see its connections and related words.

The adjective has one meaning:

Meaning #1: deficient in alertness or activity
  Synonym: unergetic
  Antonym: energetic (meaning #1)

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