There are 2 definitions of invalid in English:


Syllabification: in·va·lid
Pronunciation: /ˈinvələd


A person made weak or disabled by illness or injury: [as modifier]: an invalid husband
More example sentences
  • The resort, 1,500m above sea level, with a lake and exquisite views of the snowy mountains, has been a center for invalids and well-off hypochondriacs since the 1860s.
  • Their white colour and delicate texture have conspired to give them a reputation as a food for invalids or convalescents.
  • It did not make any mention of the fact that many of the people who have come off the unemployment benefit have casually moved over to the invalids benefit or the sickness benefit.
ill person, sick person, valetudinarian; patient, convalescent, shut-inill, sick, sickly, ailing, unwell, infirm, in poor health, indisposed; incapacitated, bedridden, housebound, frail, feeble, weak, debilitated

verb (invalids, invaliding, invalided)

[with object] Back to top  
1Remove (someone) from active service in the armed forces because of injury or illness: he was badly wounded and invalided out of the infantry
More example sentences
  • The war veteran this year won a landmark case against the Ministry of Defence because his pension had been wrongly taxed for 45 years after he was invalided out.
  • When Anna returns from digging trenches on the Luga line, and her father is invalided out of the army, they all settle in together.
  • He was invalided out of the army with a badly arthritic knee, exacerbated by his injuries.
1.1Disable (someone) by injury or illness.
More example sentences
  • He had a helicopter accident and fell 30 metres to the ground, injuring his knee and invaliding him out of the service.
  • After concussion and trench-fever on the Somme he was invalided to hospital in Edinburgh, where he was greatly encouraged in his writing by Sassoon.
  • She was invalided out of South Wales Police with a stress-related illness in 1992, after being traumatised by discovering a man who had killed himself with exhaust fumes in his car.


mid 17th century (as an adjective in the sense 'infirm or disabled'): a special sense of invalid2, with a change of pronunciation.



Pronunciation: /-ˌizəm/
More example sentences
  • Throughout his period of invalidism, McEldowney became an erudite and self-taught reader and writer.
  • Such was the milieu in which nineteenth-century gymnastics and calisthenics systems offered women palliatives for infirmities that were equated with consumptive female invalidism.
  • This gave Carl a feeling of newly won security which sustained him through his father's irritable moods, his mother's depressive invalidism, and his alienation at school.

Definition of invalid in:

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Word of the day ween
Pronunciation: wēn
be of the opinion; think or suppose

There are 2 definitions of invalid in English:


Syllabification: in·val·id
Pronunciation: /inˈvaləd


1Not valid, in particular.
More example sentences
  • Each judge, said Marei, will prepare a written statement showing figures concerning how many voters the station included, how many voted and the number of valid and invalid votes.
  • Both of these concepts undermine the ability of the working class to examine the real world around us and to differentiate between valid and invalid conclusions about it.
  • But no amount of investigation of innerworldly entities can explain the difference between truth and falsity or shed any light on the distinction between valid and invalid cognitions.
1.1(Especially of an official document or procedure) not legally recognized and therefore void because contravening a regulation or law: the vote was declared invalid due to a technicality
More example sentences
  • Mr Shipley's argument is that the defendants entered into the settlement on the basis that the patents were invalid.
  • But in truth, they are not purporting to tell the American public, say, that one of their patents is invalid or that the scope of its claims is not what it might appear to be.
  • Therefore the threats will be justified unless the patents are invalid.
(legally) void, null and void, unenforceable, not binding, illegitimate, inapplicable
1.2(Especially of an argument, statement, or theory) not true because based on erroneous information or unsound reasoning: a comparison is invalid if we are not comparing like with like
More example sentences
  • This argument is invalid, and all invalid arguments are unsound.
  • No need to be surprised - a theory is invalid if shown to be so beyond reasonable doubt.
  • Any philosopher can tell you this is an invalid argument.
false, untrue, inaccurate, faulty, fallacious, spurious, unconvincing, unsound, weak, wrong, wide of the mark, off target; untenable, baseless, ill-founded, groundless
informal full of holes
1.3(Of computer instructions, data, etc.) not conforming to the correct format or specifications.
More example sentences
  • I can't get signed into the internet it keeps saying invalid username and password.
  • Systems bound to the old version of the service suddenly find their message formats invalid.
  • Users who try to pass an invalid e-mail address are shown an error message that tells them what to change.


mid 16th century (earlier than valid): from Latin invalidus, from in- 'not' + validus 'strong' (see valid).



More example sentences
  • Initially the League of Women Voters, concerned to minimize invalidly cast ballots, opposed the paper trail, but there was a revolt in the chapters and a petition for the paper trail was signed by 800 members.
  • There is not time before February 18 for the court to reach a decision on the alliance's claim that the act was invalidly passed.
  • The trial commences with that charge invalidly joined.

Definition of invalid in: