Lethargic Meaning: Here’s What It Means and How to Use It

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Even if you don’t know the definition of lethargic, you’ve definitely experienced lethargy on multiple occasions. Lethargic is a state of being that is pretty common to the human experience. 

Because everybody experiences it at some point, the word lethargic is an important one to understand. This way, we can use it accurately to describe our situation or to understand somebody else’s. 

By the end of this comprehensive guide, you’ll have a solid understanding of this word of the day and have the confidence to integrate it into your vocabulary in writing, conversation, and more. Let’s get started. 

What Is the Definition of Lethargic? 

The word lethargic (leh thar’ jik) has a pretty simple definition:

  • Low in energy, not having the will or ability to do anything due to lack of energy, or lazy

If you’re feeling lethargic, you’re feeling tired and run down, and you may feel like you’re unable to get anything done. You might experience lethargy due to an illness or disease, like a mood disorder. You could feel lethargic due to a large, heavy meal. Other time, you just feel lethargic seemingly for no reason. 

The word lethargic could also be used to describe your brain, not just your body. If your mind is lethargic, you may be experiencing forgetfulness or sluggishness. Maybe you’re not able to think of things as quickly as you normally can. 

Other Forms of the Word

Lethargic isn’t just an adjective. The words lethargicness and lethargy are the noun forms of this word, and the word lethargically is an adverb used to describe actions.

Where Did the Word Lethargic Come From? 

To better understand the meaning of lethargic, let’s take a look at where it came from. By looking at its history, we can learn more about its meaning, definition, and how to use it. 

Most of the words in the English language are derived from either Latin or Greek. Lethargic is no exception. The word lethargic specifically comes from Greek. It then evolved through Latin and into English. Here’s how it all happened:

The word’s oldest ancestor is the word lēthargos or λήθαργος. This Greek word means “forgetfulness.” 

We can see this word in action in Greek mythology. The Greeks believed in a river called the Lethe River, also called The River of Unmindfulness or The River of Forgetfulness. This river was located in Hades, the Greek version of hell. 

When a person died, legend has it that they drink from the Lethe River, and the magical waters cause them to forget everything about their life on earth. As time went on and the legend persisted, this river eventually became associated with sluggishness. 

The word evolved eventually taking on a new form: lēthargikos. This word began to be associated with sluggishness, apathy, and laziness, perhaps due to the association with the dead. This form of the word persisted for quite a while, maintaining its spelling and meaning in Latin. 

Eventually, the word found its way into the late Middle English, spelled “lethargic.” By this point, the definition had come to fully mean “lack of energy, sluggish.” Today, it is used quite commonly in both British English and American English, despite the fact that its usage has declined over many decades. 

Other Languages

Lēthargikos also made its way into many of the other western languages, particularly the romantic languages. Modern Spanish now has the word letárgico. The French have the word léthargique. And the Portuguese of the feminine letárgica and the masculine letárgico. 

What Are Some Example Sentences for Lethargic?

Seeing the word in context can help us better understand how to use it and shed more light on its meaning. Here are some examples of sentences that use the word lethargic and its different forms:

I think I’m coming down with a cold. I’ve got a headache and congestion, and I’ve been feeling lethargic all day.

There’s just something about that Thanksgiving turkey that has me feeling so lethargic for the rest of the day. 

Some days are better than others, but for the most part, my depression has me feeling pretty lethargic all the time.

I got a write-up at work because my boss thought that I was too lethargic and wasn’t working fast enough. 

If you’re ever struggling with a little bit of lethargy, try taking a quick 15-minute power nap followed by a cup of coffee to boost your energy. 

He was lethargically raking the leaves, so I just stepped in and decided to do it myself. 

What Are the Synonyms of Lethargic? 

Here are some synonyms for the word lethargic that you might find in a thesaurus. 

  • Apathetic
  • Lazy
  • Lackadaisical 
  • Sleepy
  • Passive
  • Debilitated
  • Heavy
  • Inactive
  • Drowsy
  • listless

What Are its Antonyms? 

Here are some antonyms for the word lethargic.

  • Active
  • Alert
  • Lively
  • Energetic
  • Vivacious
  • Enthusiastic
  • Animated

The Word Lethargic 

The word lethargic is very useful. It can be helpful in describing medical symptoms to a doctor or psychologist, and it can also be useful in everyday conversation to describe how a person is feeling or behaving. 

Now, you have a full understanding of the word lethargic, its meaning, and how to use it. Use it confidently in your writing and speech. If you ever need a refresher on the word lethargic, just come back to this article for all the information that you need. 


Definition of lethargy | NCI Dictionary of Cancer Terms 

LETHARGIC | Cambridge English Dictionary 

Lethe | Facts, Information, and Mythology | Pantheon