Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “invalid”


noun [C]     /ˈɪn.və.lɪd/ old-fashioned
someone who is sick and unable to take care of himself or herself, especially for a long time: Is the invalid in bed?Handicap and the disabledPeople who receive medical treatment
(Definition of invalid noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of invalid

Definitions of “invalid” in other dictionaries

Word of the Day


a document given to students or reporters which contains information about a particular subject

Word of the Day


Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More