The word for today is…
lexicographer (noun):
: an author or editor of a dictionary
Source : Merriam -Webster
Etymology : The ancient Greeks were some of the earliest makers of dictionaries; they used them mainly to catalog obsolete terms from their rich literary past. To create a word for writers of dictionaries, the Greeks sensibly attached the suffix -graphos, meaning “writer,” to lexikon, meaning “dictionary,” to form lexikographos, the direct ancestor of the English word lexicographer. Lexikon, which itself descends from Greek lexis (meaning “word” or “speech”), also gave us lexicon, which can mean either “dictionary” or “the vocabulary of a language, speaker, or subject.”
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