invalid

¹

[in-vuh-lid]

noun

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)

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.

1. to become an invalid.

invalid

²

[in-val-id]

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

/ ˈɪnvəˌliːd, -lɪd /

noun

1. 1. a person suffering from disablement or chronic ill health

   2. ( as modifier )

      an invalid chair

adjective

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

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

invalid

²

/ 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

Usage

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

Other Word Forms

• invalidly adverb
• invalidness noun
• invalidity noun

Word History and Origins

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”; invalid ¹

Word History and Origins

Origin of invalid¹

C17: from Latin invalidus infirm, from _in- ¹ + validus strong

Origin of invalid²

C16: from Medieval Latin invalidus without legal force; see _invalid ¹

Example Sentences

"Labelling ships used to export Russian oil as 'shadow fleet' is discriminatory and misleading," the embassy said, and instances of invalid flags were typically down to "easily resolved" issues such as administrative delays.

Read more on BBC

Other times the princess would watch from her wheeled invalid chair as Penelope sewed.

Read more on Literature

“Accordingly, the challenged laws are invalid under the Supremacy Clause and their application to the Federal Government should be preliminarily and permanently enjoined.”

Read more on Los Angeles Times

If they don't agree to the transfer, judges can appeal to the judicial commission and if their reasons for not moving are found invalid the judge would have to retire.

Read more on BBC

The novel relates the partly autobiographical story of Charley Klein, who is raised in community housing in the Bronx, N.Y., in the 1930s by an overworked mother and a resentful, invalid father.

Read more on The Wall Street Journal

Related Words

• baseless 
• false 
• inoperative 
• irrational 
• null 
• unfounded 
• unreasonable 
• unscientific 
• unsound 
• untrue