invalid

1 of 4

adjective (1)

in·​val·​id (ˌ)in-ˈva-ləd How to pronounce invalid (audio)
: not valid:
a
: being without foundation or force in fact, truth, or law
an invalid assumption
declared the will invalid
b
: logically inconsequent
invalidly adverb

invalid

2 of 4

noun

in·​va·​lid ˈin-və-ləd How to pronounce invalid (audio)
 British usually  -ˌlēd
: one who is sickly or disabled

invalid

3 of 4

verb

in·​va·​lid ˈin-və-ləd How to pronounce invalid (audio)
-ˌlid,
 British usually  -ˌlēd,
 or  ˌin-və-ˈlēd
invalided; invaliding; invalids

transitive verb

1
: to remove from active duty by reason of sickness or disability
2
: to make sickly or disabled

invalid

4 of 4

adjective (2)

in·​va·​lid ˈin-və-ləd How to pronounce invalid (audio)
 British usually  -ˌlēd
1
: affected by disease or disability : sickly
2
: of, relating to, or suited to one that is sick
an invalid chair

Examples of invalid in a Sentence

Adjective (1) the treaty is invalid once one side violates it that's an invalid assumption on your part an argument which has one untrue premise is invalid an invalid claim that can be easily disproved by the facts Noun Her husband has become an invalid. Adjective (2) an old and now invalid woman who rarely gets out anymore
Recent Examples on the Web
Adjective
However, after checking the ID, Ammerman found the ID was invalid and that Roberts did not have a license in either state. Michael Dorgan, Fox News, 12 July 2024 If any portion hereof is held invalid or unenforceable, the remainder of the disclaimer shall nonetheless remain in full force and effect. Usa Today Staff, USA TODAY, 24 June 2024
Noun
Concern grew that the fabulous invalid, as the theater has long been dubbed, might be down for the count. Charles McNulty, Los Angeles Times, 4 Dec. 2023 As these invalids made their way to Portsmouth, nearly half slipped away, including one who hobbled off on a wooden leg. David Grann, The New Yorker, 28 Feb. 2023 See all Example Sentences for invalid 

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

Word History

Etymology

Adjective (1)

Latin invalidus weak, from in- + validus strong — more at valid

Adjective (2)

Latin & French; French invalide, from Latin invalidus

First Known Use

Adjective (1)

1542, in the meaning defined above

Noun

1701, in the meaning defined above

Verb

1787, in the meaning defined at sense 1

Adjective (2)

1642, in the meaning defined at sense 1

Time Traveler
The first known use of invalid was in 1542

Dictionary Entries Near invalid

Cite this Entry

“Invalid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/invalid. Accessed 20 Jul. 2024.

Kids Definition

invalid

1 of 4 adjective
in·​val·​id (ˈ)in-ˈval-əd How to pronounce invalid (audio)
: having no force or effect : not valid
an invalid parking sticker
an invalid assumption
invalidity
ˌin-və-ˈlid-ət-ē
noun
invalidly adverb

invalid

2 of 4 adjective
in·​va·​lid ˈin-və-ləd How to pronounce invalid (audio)
1
: suffering from disease or disability : sickly
2
: of, relating to, or suited to an invalid

invalid

3 of 4 noun
like 2
 How to pronounce invalid (audio)
: one who is sickly or disabled

invalid

4 of 4 verb
in·​va·​lid ˈin-və-ləd How to pronounce invalid (audio)
-ˌlid
: to make sickly or disabled
Etymology

Adjective

from earlier invalid "not having a sound basis in fact or reason, not valid," from Latin invalidus "weak"

Adjective

from French invalide "suffering from a disease, sickly," from Latin invalidus "weak"

Medical Definition

invalid

1 of 3 adjective
in·​va·​lid
ˈin-və-ləd, British usually -ˌlēd
1
: affected by disease or disability : sickly
2
: of, relating to, or suited to one that is sick
an invalid chair

invalid

2 of 3 noun
: one who is sickly or disabled

invalid

3 of 3 transitive verb
in·​va·​lid
ˈin-və-ləd, -ˌlid, British usually -ˌlēd or ˌin-və-ˈlēd
1
: to remove from active duty by reason of sickness or disability
was invalided out of the army
2
: to make sickly or disabled
a patient invalided by valvular disease

Legal Definition

invalid

adjective
in·​val·​id in-ˈva-ləd How to pronounce invalid (audio)
: being without force or effect under the law
declared the will invalid
invalidly adverb

More from Merriam-Webster on invalid

Last Updated: - Updated example sentences
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