lexicon (noun) - wordbook or dictionary; the vocabulary of a particular language, field, or social class [lek-si-kon]
BREAKDOWN: LEX- (word) + -ICON (book)
lexicology is the study of the formation, meaning, and use of words and of idiomatic combinations of words
a lexicologist is a compiler or writer of a dictionary or a student of the lexical component of language
“We open our mouths and out flow words whose ancestries we do not even know. We are walking lexicons. In a single sentence of idle chatter we preserve Latin, Anglo-Saxon, Norse: we carry a museum inside our heads, each day we commemorate peoples of whom we have never heard.” —Penelope Lively