Invalid

[in-vuh-lid; British in-vuh-leed] /ˈɪn və lɪd; British ˈɪn vəˌlid/

noun
1.
an infirm or sickly person.
2.
a person who is too sick or weak to care for himself or herself:
My father was an invalid the last ten years of his life.
3.
Archaic. a member of the armed forces disabled for active service.
adjective
4.
unable to care for oneself due to infirmity or disability:
his invalid sister.
5.
of or for invalids:
invalid diets.
6.
(of things) in poor or weakened condition:
the invalid state of his rocking chair.
verb (used with object)
7.
to affect with disease; make an invalid:
He was invalided for life.
8.
to remove from or classify as not able to perform active service, as an invalid.
9.
British. to remove or evacuate (military personnel) from an active theater of operations because of injury or illness.
verb (used without object), Archaic.
10.
to become an invalid.
[in-val-id] /ɪnˈvæl ɪd/
adjective
1.
not valid; without force or foundation; indefensible.
2.
deficient in substance or cogency; weak.
3.
void or without legal force, as a contract.
/ˈɪnvəˌliːd; -lɪd/
noun
1.

adjective
2.
suffering from or disabled by injury, sickness, etc
verb (transitive)
3.
to cause to become an invalid; disable
4.
(usually foll by out; often passive) (mainly Brit) to require (a member of the armed forces) to retire from active service through wounds or illness
/ɪnˈvælɪd/
adjective
1.
not valid; having no cogency or legal force
2.
(logic) (of an argument) having a conclusion that does not follow from the premises: it may be false when the premises are all true; not valid
adj.

“not strong, infirm,” 1640s, from Latin invalidus “not strong, infirm, weak, feeble,” from in- “not” (see in- (1)) + validus “strong” (see valid). Specific meaning “infirm from sickness, disease, or injury” is from 1640s.

“of no legal force,” 1630s, from special use of Latin invalidus (see invalid (adj.1)).
n.

1709, originally of disabled military men, from invalid (adj.1). Invalides is short for French Hôtel des Invalides, home for old and disabled soldiers in the 7th arrondissement of Paris.

invalid in·va·lid1 (ĭn’və-lĭd)
n.
One who is incapacitated by a chronic illness or disability. adj.
Incapacitated by illness or injury.