Other Word Forms
Etymology
Origin of lethargic
First recorded in 1350–1400; from Latin lēthargicus, from Greek lēthargikós; replacing Middle English litargik, from Medieval Latin litargicus ( see lethargy, -ic)
Compare meaning
How does lethargic compare to similar and commonly confused words? Explore the most common comparisons:
Explanation
When you feel lethargic, you're sluggish or lacking energy. Being sleepy or hungry can make anyone lethargic. Being lethargic makes it hard to get anything done: you feel weak and sleepy. Whatever the reason, a lethargic person needs to snap out of it and get some energy, maybe by eating something or by taking a nap. Being lethargic also goes well with watching TV, since that takes almost no energy at all. When you feel lethargic, you don't have any energy to spare.
Vocabulary lists containing lethargic
ASVAB Word Knowledge
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Essential Academic Vocabulary for High School Students, List 3
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
ACT Vocabulary List
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Hot weather can make you feel tired and lethargic during the day.
From BBC ● Jun. 22, 2026
Many taking weight-loss medications initially lose fat and feel great, but quickly start to feel weak and lethargic, he said.
From The Wall Street Journal ● May 17, 2026
“Woods’ movement was lethargic and slow,” sheriff’s deputy Tatiana Levenar wrote in the report.
From Los Angeles Times ● Mar. 31, 2026
That show is growing duller, and more lethargic and repetitive, by the day, like watching reruns of a canceled sitcom.
From Salon ● Feb. 13, 2026
The nondemanding, lethargic nature of the classes he was in made it difficult to fault his attitude about school.
From "Friday Night Lights: A Town, A Team, And A Dream" by H.G. Bissinger
![]()
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.