BrE BrE//ˈɪnvəlɪd//; NAmE NAmE//ˈɪnvəlɪd//; BrE BrE//ˈɪnvəliːd//; NAmE NAmE//ˈɪnvəliːd//a person who needs other people to take care of them, because of illness that they have had for a long time She had been a delicate child and her parents had treated her as an invalid. his invalid wife He was found guilty of murdering his invalid father. Her husband was an invalid and couldn’t come to the door to open it. See related entries: Injuries Word Originnoun mid 17th cent. (as an adjective in the sense ‘infirm or disabled’): a special sense of invalid (adjective), with a change of pronunciation.