lexicon

 
Pronunciation: /ˈlɛksɪk(ə)n/

noun

  • the vocabulary of a person, language, or branch of knowledge: the size of the English lexicon
  • a dictionary, especially of Greek, Hebrew, Syriac, or Arabic: a Greek-Latin lexicon

Origin:

early 17th century: modern Latin, from Greek lexikon (biblion) '(book) of words', from lexis 'word', from legein 'speak'