vocabulary

n. stock of words used by an individual or existing in a language, lexicon; list of words and their definitions in alphabetical order (especially for the purpose of learning)

A vocabulary is a set of words known to a person or other entity, or that are part of a specific language.The vocabulary of a person is defined either as the set of all words that are understood by that person or the set of all words likely to be used by that person when constructing new sentences. So "curse" is a regular part of the vocabulary of native English speakers but "imprecate" is not, even though the two words are synonyms. The richness of a person's vocabulary is popularly thought to be a reflection of intelligence or level of education. Accordingly, many standardised tests, such as the SAT, have questions that test vocabulary.
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(n.)
A sum or stock of words employed.
  

(n.)
A list or collection of words arranged in alphabetical order and explained; a dictionary or lexicon, either of a whole language, a single work or author, a branch of science, or the like; a word-book.
  

Noun
1. a listing of the words used in some enterprise
(hypernym) wordbook
2. a language user's knowledge of words
(synonym) lexicon, mental lexicon
(hypernym) cognition, knowledge, noesis
(part-holonym) language, speech
3. the system of techniques or symbols serving as a means of expression (as in arts or crafts); "he introduced a wide vocabulary of techniques"
(hypernym) frame of reference
(classification) art, artistic creation, artistic production