I. in ‧ val ‧ id 1 /ɪnˈvæləd, ɪnˈvælɪd/ BrE AmE adjective
[ Word Family: verb : ↑ validate ≠ ↑ invalidate ; noun : ↑ validity ≠ ↑ invalidity ; adjective : ↑ valid ≠ ↑ invalid ]
[ Date: 1500-1600 ; Language: Latin ; Origin: invalidus , from validus ; ⇨ ↑ valid ]
1 . a contract, ticket, claim etc that is invalid is not legally or officially acceptable OPP valid :
Without the right date stamped on it, your ticket will be invalid.
2 . an argument, reason etc that is invalid is not based on true facts or clear ideas, and lacks good judgment OPP valid
3 . if something you type into a computer is invalid, the computer does not recognize or accept it:
Filename in invalid format.
II. in ‧ va ‧ lid 2 /ˈɪnvəliːd, -ləd $ -ləd/ BrE AmE noun [countable]
[ Date: 1600-1700 ; Language: French ; Origin: invalide , from Latin invalidus ; ⇨ ↑ invalid 1 ]
someone who cannot look after themselves because of illness, old age, or injury:
I resented being treated as an invalid.
—invalid adjective [only before noun]
III. in ‧ va ‧ lid 3 BrE AmE verb
be invalided out ( also be invalided home ) phrasal verb British English
to have to leave the army, navy etc because you are ill or injured