Lexicography
Lexicography is the study of lexicons and the art of compiling dictionaries. It is divided into two separate academic disciplines:

Practical lexicography is the art or craft of compiling, writing and editing dictionaries. Theoretical lexicography is the scholarly study of semantic, orthographic, syntagmatic and paradigmatic features of lexemes of the lexicon (vocabulary) of a language, developing theories of dictionary components and structures linking the data in dictionaries, the needs for information by users in specific types of situations, and how users may best access the data incorporated in printed and electronic dictionaries. This is sometimes referred to as "metalexicography". There is some disagreement on the definition of lexicology, as distinct from lexicography.