1

invalid

adjective in·val·id \ (ˌ)in-ˈva-ləd \

Definition of invalid

:not valid:
a :being without foundation or force in fact, truth, or law
  • an invalid assumption
  • declared the will invalid
b :logically inconsequent

invalidly

play \(ˌ)in-ˈva-ləd-lē\ adverb

Origin and Etymology of invalid

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


2

invalid

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

Definition of invalid

1 :suffering from disease or disability :sickly
2 :of, relating to, or suited to one that is sick
  • an invalid chair

Origin and Etymology of invalid

Latin & French; French invalide, from Latin invalidus


3

invalid

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

Definition of invalid

:one who is sickly or disabled

Examples of invalid in a Sentence

  1. Her husband has become an invalid.

First Known Use of invalid

1701


4

invalid

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

Definition of invalid

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

First Known Use of invalid

1787


INVALID Defined for English Language Learners

invalid

noun

Definition of invalid for English Language Learners

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


invalid

verb

Definition of invalid for English Language Learners

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


INVALID Defined for Kids

1

invalid

adjective in·val·id \ in-ˈva-ləd \

Definition of invalid for Students

:having no force or effect

2

invalid

noun in·va·lid \ ˈin-və-ləd \

Definition of invalid for Students

:a person suffering from sickness or disability

Medical Dictionary

1

invalid

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

medical Definition of invalid

1 :suffering from disease or disability :sickly
2 :of, relating to, or suited to one that is sick
  • an invalid chair

2

invalid

noun

medical Definition of invalid

:one who is sickly or disabled

3

invalid

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

medical Definition of invalid

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

Law Dictionary

invalid

adjective in·val·id \ in-ˈva-ləd \

legal Definition of invalid

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

invalidly

adverb


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