Lexicography

n. process of writing or compiling a dictionary

For the term in mathematics, see Lexicographical order The pursuit of lexicography is divided into two related disciplines:Practical lexicography is the art or craft of compiling, writing and editing dictionaries.Theoretical lexicography is the scholarly discipline of analyzing and describing the semantic, syntagmatic and paradigmatic relationships within the lexicon (vocabulary) of a language and developing theories of dictionary components and structures linking the data in dictionaries. This is sometimes referred to as metalexicography.
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(n.)
The art, process, or occupation of making a lexicon or dictionary; the principles which are applied in making dictionaries.
  

Noun
1. the act of writing dictionaries
(hypernym) writing, authorship, composition, penning