invalid
Definitions
Not legally or officially acceptable; no longer in force
无效的，失效的
Not logically sound; not based on good reasoning
站不住脚的，无根据的
A person made weak by long illness or disability
病弱者，伤残者
Root Breakdown
Root-derivedin- (not) + valid (strong, standing) = 'not standing.' An invalid argument collapses; an invalid pass won't be accepted. The noun invalid (a sick person) is the same word: someone whose body is 'not strong' — note the stress shifts.
Usage Guide
Watch the stress: the adjective is in-VAL-id (/ɪnˈvælɪd/, 'not valid'); the noun for a sick person is IN-va-lid (/ˈɪnvəlɪd/). Same spelling, different stress and meaning. The 'sick person' noun is now dated and can sound offensive — prefer 'person with a disability.'
Example Sentences
- 1.
Your password is invalid; please try again.
- 2.
The court ruled that the contract was invalid.