invalid

adjective (1)
in·val·id | \(ˌ)in-ˈva-ləd \

Definition of invalid 

(Entry 1 of 4)

: not valid:

a : being without foundation or force in fact, truth, or law an invalid assumption declared the will invalid

b : logically inconsequent

invalid

adjective (2)
in·va·lid | \ˈin-və-ləd, British usually -ˌlēd\

Definition of invalid (Entry 2 of 4)

1 : suffering from disease or disability : sickly

2 : of, relating to, or suited to one that is sick an invalid chair

invalid

noun
\ˈin-və-ləd, British usually -ˌlēd\

Definition of invalid (Entry 3 of 4)

: one who is sickly or disabled

invalid

verb
in·va·lid | \ˈin-və-ləd, -ˌlid, British usually -ˌlēd or ˌin-və-ˈlēd\
invalided; invaliding; invalids

Definition of invalid (Entry 4 of 4)

transitive verb

1 : to remove from active duty by reason of sickness or disability

2 : to make sickly or disabled

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Other Words from invalid

Adjective (1)

invalidly \(ˌ)in-ˈva-ləd-lē \ adverb

Examples of invalid in a Sentence

Noun

Her husband has become an invalid.

First Known Use of invalid

Adjective (1)

1542, in the meaning defined above

Adjective (2)

1642, in the meaning defined at sense 1

Noun

1701, in the meaning defined above

Verb

1787, in the meaning defined at sense 1

History and Etymology for invalid

Adjective (1)

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

Adjective (2)

Latin & French; French invalide, from Latin invalidus

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Statistics for invalid

Look-up Popularity

Time Traveler for invalid

The first known use of invalid was in 1542

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More Definitions for invalid

invalid

noun

English Language Learners Definition of invalid

 (Entry 1 of 2)

: a person who needs to be cared for because of injury or illness

invalid

verb

English Language Learners Definition of invalid (Entry 2 of 2)

: to release (someone) from active military service because of illness or injury

invalid

adjective
in·val·id | \in-ˈva-ləd \

Kids Definition of invalid

 (Entry 1 of 2)

: having no force or effect

invalid

noun
in·va·lid | \ˈin-və-ləd \

Kids Definition of invalid (Entry 2 of 2)

: a person suffering from sickness or disability

invalid

adjective
in·va·lid | \ˈin-və-ləd, British usually -ˌlēd\

Medical Definition of invalid 

(Entry 1 of 3)

1 : suffering from disease or disability : sickly

2 : of, relating to, or suited to one that is sick an invalid chair

invalid

noun

Medical Definition of invalid (Entry 2 of 3)

: one who is sickly or disabled

invalid

transitive verb
in·va·lid | \ˈin-və-ləd, -ˌlid, British usually -ˌlēd or ˌin-və-ˈlēd\

Medical Definition of invalid (Entry 3 of 3)

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

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invalid

adjective
in·val·id | \in-ˈva-ləd \

Legal Definition of invalid 

: being without force or effect under the law declared the will invalid

Other Words from invalid

invalidly adverb

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Comments on invalid

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WORD OF THE DAY

to reject or criticize sharply

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