case-sensitive

adjective

case-sen·​si·​tive ˈkās-ˈsen(t)-sə-tiv 

-ˈsen(t)s-təv

: requiring correct input of uppercase and lowercase letters

Having the Caps Lock key on accidentally can also lead to a frustrating series of "wrong password" alerts when trying to use a case-sensitive password for your office network or Internet provider.

—J. D. Biersdorfer

Word History

First Known Use

1981, in the meaning defined above