INVALID

Of no force, weight, or cogency; not valid; weak.

Having no force, effect, or efficacy; void; null; as, an invalid contract or agreement.

A person who is weak and infirm; one who is disabled for active service; especially, one in chronic ill health.

Not well; feeble; infirm; sickly; as, he had an invalid daughter.

To make or render invalid or infirm. "Invalided, bent, and almost blind." Dickens.

To classify or enroll as an invalid. Peace coming, he was invalided on half pay. Carlyle.