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Synonyms

invalid

1 American  
[in-vuh-lid] / ˈɪn və lɪd /

noun

  • invalids
    plural
  1. an infirm or sickly person.

  2. a person who is too sick or weak to take care of their own needs.

    My father was an invalid the last ten years of his life.

  3. Archaic. a member of the armed forces disabled for active service.


adjective

  1. unable to care for oneself due to infirmity or disability.

    his invalid sister.

  2. of or for invalids.

    invalid diets.

  3. (of things) in poor or weakened condition.

    the invalid state of his rocking chair.

verb (used with object)

  • invalids,
    present (3rd person singular)
  • invalided,
    past participle,  past
  • invaliding
    present participle
  1. to affect with disease; make an invalid.

    He was invalided for life.

  2. to remove from or classify as not able to perform active service, as an invalid.

  3. British. to remove or evacuate (military personnel) from an active theater of operations because of injury or illness.

verb (used without object)

Archaic.
  • invalids,
    present (3rd person singular)
  • invalided,
    past participle,  past
  • invaliding
    present participle
  1. to become an invalid.

invalid 2 American  
[in-val-id] / ɪnˈvæl ɪd /

adjective

  1. not valid; not founded in truth, fact, or logic, and hence weak and indefensible; unsound; untenable.

    The entire argument depends on an invalid assumption.

    Synonyms:
    incorrect, inaccurate, false, erroneous, unsubstantiated, unfounded, groundless, baseless
  2. deficient in effectiveness; inadequate.

    Self-perception is an invalid method of judging one's own biases.

  3. void or without legal force, as a contract.

    Without the grandfather clause, thousands of such warranties would now be invalid. The coupon is invalid in our state.

    Synonyms:
    null and void
  4. not accepted or permitted because a required element or the necessary form is lacking; not usable.

    Anything with fewer than five characters is an invalid password, and you’ll get an error message prompting you to pick something more secure.


invalid 1 British  
/ ˈɪnvəˌliːd, -lɪd /

noun

    1. a person suffering from disablement or chronic ill health

    2. ( as modifier )

      an invalid chair

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. suffering from or disabled by injury, sickness, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to cause to become an invalid; disable

  2. (usually foll by out; often passive) to require (a member of the armed forces) to retire from active service through wounds or illness

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
invalid 2 British  
/ ɪnˈvælɪd, ˌɪnvəˈlɪdɪtɪ /

adjective

  1. not valid; having no cogency or legal force

  2. logic (of an argument) having a conclusion that does not follow from the premises: it may be false when the premises are all true; not valid

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

It is best to avoid using the term invalid when referring to people with chronic illnesses or disabilities

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of invalid1

First recorded in 1635–45; from French invalide, from Latin invalidus “weak, feeble, infirm”; See in- 3, valid

Origin of invalid2

First recorded in 1630–40; from Latin invalidus “weak, feeble”; see invalid 1

Explanation

A person who is very sick or injured and needs frequent care is an invalid. Also, something no longer current or useful is invalid. The main uses of this word have to do with people and things that don't work very well anymore. A driver's license that has expired is invalid — it needs to be renewed. If you lost your health insurance, it's invalid. People who are called invalids are disabled or incapacitated severely. Be careful with this word, because some think it is inappropriate, since it sounds as if some people are not as valid as others based on physical capability.

Keep Reading on Vocabulary.com

Vocabulary lists containing invalid

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.

See Examples For:

But Florida Attorney General James Uthmeier nonetheless sought to intervene in Simpson’s case, arguing in filings that the surrogacy agreement was invalid and Zhou hadn’t proved parentage under Florida law.

From The Wall Street Journal Jul. 31, 2026

Bar-licensed attorneys have also tried to fast-track the system, filing invalid for asylum or lawful permanent residency applications for unknowing clients.

From Los Angeles Times Jul. 31, 2026

Even if your grandmother changed her will because she was tired of arguing with your father, that doesn’t automatically make the change legally or morally invalid.

From MarketWatch Jul. 6, 2026

The Vatican said on Thursday: "The sacred ministers of the Society of St Pius X administer the sacraments illicitly, while the sacrament of penance they administer and the marriages they witness are invalid."

From BBC Jul. 2, 2026

“I can’t! I give up! I don’t care! I want to go back to bed and be an invalid for the rest of my life!!”

From "Lucky Broken Girl" by Ruth Behar

If you are one of those who don't need Vegemite medicinally, the thousands of invalids and babies are asking you to deny yourself of it for the time being.

From Salon Jul. 10, 2023

Patient outcomes varied depending on whether you asked the officer who lost fighters, the ferryman who shuttled the sick, the doctor who treated invalids or the adjutant who buried bodies.

From Scientific American Jul. 23, 2022

Pandemics, mansions, triangles, illnesses, abandonments, deaths, letters and inheritances also kaleidoscopically reappear, as do grandfathers, lovers, invalids, caretakers, utopians and more.

From New York Times Jan. 7, 2022

Wealthy invalids flocked to the south Devon town for its sunshine and sea air.

From The Guardian Feb. 15, 2021

By this time, Vincent and McNeish were complete invalids and stayed in the cave in a stupor.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong

Once a defender, he was invalided out of the game with an ACL injury at 21.

From BBC Oct. 20, 2025

Last August, the U.S. military’s top appeals court upheld Bergdahl’s conviction, rejecting arguments that public comments by Trump and McCain should have invalided his prosecution, Military.com reported.

From Fox News Feb. 18, 2021

He knows that the old songs give “the invalided and senile a musical opportunity to re-court their wives, re-raise their children and re-fight their wars.”

From New York Times Sep. 21, 2017

Just as Connie Willis salutes the resilience of Brits in her fiction about England during World War II, Kowal pays similar tribute in this novel through her depiction of grandmotherly Mrs. Richardson and invalided Lt.

From Seattle Times Sep. 4, 2016

General Temple, a few days after the party, fell a victim to a seductive pudding prepared by Delilah, and was immediately invalided with the gout.

From Throckmorton by Molly Elliot Seawell

There he called on Senator James A. .Reed of Missouri, who is invaliding from a recent illness.

From Time Magazine Archive

The next in seniority was entirely adverse to the invaliding, as, without he could invalide too, he would have to go to the West Indies in the place of our surgeon.

From Rattlin the Reefer by Frederick Marryat

This was the first time Aubrey had been considered in condition for such festivities, and the gratification of being superior to somebody might account for his glee in invaliding his friend.

From The Trial by Charlotte Mary Yonge

In hospital they are always professing to a recovery from fever that their pallid faces and enlarged spleens belie, and they take not kindly to any suggestion of invaliding.

From Sketches of the East Africa Campaign by Robert Valentine Dolbey

But he was of those who do not take kindly to invaliding.

From Sketches of the East Africa Campaign by Robert Valentine Dolbey

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