adjective
- not legally or officially acceptable; not valid
- not based on correct reasoning or facts; not sound
noun
- a person who is weakened or disabled by illness or injury
Usage: somewhat dated
Examples
- The contract was declared invalid due to missing signatures.
- Your parking ticket is invalid because the meter was broken.
- His argument is invalid because it’s based on false assumptions.
- The test results are invalid due to contaminated samples.
- She cared for her invalid mother for many years.
- The invalid required constant medical attention.
- Without proper documentation, your claim is invalid.