las·​si·​tude ˈla-sə-ˌtüd How to pronounce lassitude (audio)
: a condition of weariness or debility : fatigue
The patient complained of headache, nausea, and lassitude.
: a condition characterized by lack of interest, energy, or spirit : languor
surrendered to an overpowering lassitude, an extreme desire to sit and dreamAlan Moorehead

Did you know?

Sick and Tired: The Literal and Figurative Meanings of Lassitude

Lassitude and weariness make an interesting pair. As with many nearly synonymous pairs of words in English, one is derived from Latin and the other from Old English. Even though they both mean “the condition of being tired,” they are used in different ways. Following a common pattern, the Latinate word tends to be used in technical, medical, and formal writing, and the Old English-derived word is used when referring to physical, emotional, and spiritual qualities.

Lassitude comes from the Latin word lassus, meaning “weary.” Our English spelling comes from the French word that developed directly from Latin, borrowed in the 15th century. In French, the word las (masculine) or lasse (feminine) means “weary” or “tired,” and the idiom être las de means “to be sick and tired of.” This led to another English word with the same root: alas, a word that expresses sadness or disappointment, but conveys some measure of fatigue and resignation as well.

Though it sometimes is just a fancy word for fatigue in medical contexts, lassitude is also used in ways that are metaphorical and closer in meaning to “negligence”:

Congress was being choked by pettiness and lassitude.

The case was delayed because of sheer lassitude.

The failure was the result of moral lassitude.

Choose the Right Synonym for lassitude

lethargy, languor, lassitude, stupor, torpor mean physical or mental inertness.

lethargy implies such drowsiness or aversion to activity as is induced by disease, injury, or drugs.

months of lethargy followed my accident

languor suggests inertia induced by an enervating climate or illness or love.

languor induced by a tropical vacation

lassitude stresses listlessness or indifference resulting from fatigue or poor health.

a depression marked by lassitude

stupor implies a deadening of the mind and senses by shock, narcotics, or intoxicants.

lapsed into an alcoholic stupor

torpor implies a state of suspended animation as of hibernating animals but may suggest merely extreme sluggishness.

a once alert mind now in a torpor

Examples of lassitude in a Sentence

Symptoms of the disease include paleness and lassitude. our lassitude was such that we couldn't even be bothered to get more soda from the fridge
Recent Examples on the Web Pence says that Biden’s lassitude on Ukraine is connected to his disastrous withdrawal from Afghanistan, his foolish pursuit of a nuclear deal with Iran, and his recent turn toward dovishness on China. Matthew Continetti, National Review, 8 July 2023 Men struggled to defeat lassitude and depression. Alex Kershaw, WSJ, 7 Sep. 2022 Most of the youthful actors give performances of a startling lassitude, although, to be charitable, that may be the fault of the plot—specifically, of the Blue, a nasty drink, vaguely reminiscent of toilet cleaner, which all the growing kids are required to swig. Anthony Lane, The New Yorker, 16 Apr. 2021 Founded by LeRoi Jones (no relation), who combined immense talent, critical acumen, and, after being brutalized by the police, a rusty shank of disdain for the lassitude of white America, the movement advanced the idea that white people’s approval was beside the point. Calvin Baker, The Atlantic, 2 Aug. 2020 Rather than solely signifying the cursed lassitude of middle-aged masculinity, the term can also gesture at something both self-conscious and fashionably nostalgic. Phillip MacIak, The New Republic, 27 June 2022 This could be due to lassitude or desire to shirk responsibility for tough questions. Mark Medish, The New Republic, 30 Nov. 2022 But despite these peaks, the city still feels off, gnawed by anxiety, lassitude, and resignation. Curbed, 15 Dec. 2022 Today, paralyzing lassitude is often seen as a symptom of disease rather than of turpitude. Kat McGowan, Discover Magazine, 25 Mar. 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'lassitude.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Middle English, from Latin lassitudo, from lassus weary; probably akin to Old English læt late — more at late

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of lassitude was in the 15th century

Dictionary Entries Near lassitude

Cite this Entry

“Lassitude.” Dictionary, Merriam-Webster, Accessed 11 Dec. 2023.

Kids Definition


las·​si·​tude ˈlas-ə-ˌt(y)üd How to pronounce lassitude (audio)
: a condition of weariness : fatigue
: a state of dreamy idleness : languor

Medical Definition


las·​si·​tude ˈlas-ə-ˌt(y)üd How to pronounce lassitude (audio)
: a condition of weariness, debility, or fatigue
a disease typically accompanied by chronic lassitude

More from Merriam-Webster on lassitude

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!