Vocabulary is all about words — the words in a language or a special set of words you are trying to learn. Vocabulary is so important, we even created a web site to help expand yours.
First used in the 1500s to mean a list of words with explanations, the noun vocabulary came to refer to the “range of language of a person or group” about two hundred years later. A lot of hobbies, like fishing or knitting, require that you learn their unique vocabulary before you can get the most out of them. If you're in a rush, vocab is a faster way to say vocabulary.