"uppercase letter" is correct and usable in written English.
It is an informal term used to refer to a capital letter. For example: "The first letter of his name is an uppercase letter."
The stylebook advises, "Ordinarily close up compounds formed with pre unless the prefix is directly followed by an e or an uppercase letter".
I had been hunched over my computer all afternoon in a panic, racking my brain for something, anything that still made sense and was at least eight characters long with one uppercase letter and one number.
She also dumps all of the story's occult power on a boarded-up dwelling known as the House: beware of an uppercase letter that is used for unexplained aggrandizement.
Vector and matrix are denoted by a boldface lowercase letter and a boldface uppercase letter, respectively.
Since nouns start with an uppercase letter in German, they could automatically be identified.
F... a Fourier transform is denoted by an uppercase letter with a greek letter index.
The uppercase letters, he said.
Attached to the handle was a tag that read in black uppercase letters: "RUSH".
We are ready to believe again" in red and black uppercase letters.
" The Mets wore cream-colored retro-style uniforms with "New York" stenciled in uppercase letters across the front.
"They can't always count on 12 uppercase letters, three lowercase letters, two punctuation marks and a percent symbol".
