- invalid in‧val‧id [ɪnˈvæld] adjective1. LAW an invalid contract, agreement, document etc is not legally or officially acceptable:
• Wellcome's patent to the drug was ruled invalid because the company didn't invent the compound.
• evidence obtained using invalid warrants2. not based on true facts and therefore not right:
• The promotions lacked balance and made invalid comparisons between rival products.3. COMPUTING if something that you type into a computer is invalid, the computer does not recognize or accept it:
• The date is in an invalid format.— invalidity noun [uncountable] :
• The bonds are perforated with small holes to show their invalidity.
* * *invalidity UK US /ˌɪnvəˈlɪdəti/ noun [U]► the fact of not being legally or officially acceptable: »
The company was fully aware of the invalidity of its patent.► GOVERNMENT the condition of being unable to work because of health problems, and receiving money from a government or organization because of this : »
The ex-soldier receives an invalidity pension from the Army.
Financial and business terms. 2012.