Noun
one of the large alphabetic characters used as the first letter in writing or printing proper names and sometimes for emphasis
Source: WordNetIn physics, I sprung on him as we sat in the Taco Bell drive-through, what does the capital letter W stand for? Sarah Dessen
Sure, women sportswriters look when they're in the clubhouse. Read their stories. How else do you explain a capital letter in the middle of a word? Bob Uecker
Fanfiction isn't copying - it's a. One long party, from the first capital letter to the last full stop! Jasper Fforde
printers once kept the type for capitals and for small letters in separate cases; capitals were kept in the upper half of the type case and so became known as upper-case letters Source: Internet