lexicographer n.

c. 1600, "a dictionary, a word-book," from French lexicon or directly from Modern Latin lexicon, from Greek lexikon (biblion) "word (book)," from neuter of lexikos "pertaining to words," from lexis "a word, a phrase; reason; way of speech, diction, style," from legein "to say" (from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')").

Especially of dictionaries of Greek, Syriac, Hebrew, or Arabic, because these typically were written in Latin, and in Modern Latin lexicon (not dictionarius) was the preferred name for a word-book. The modern sense of "vocabulary proper to some sphere of activity" (1640s) is a figurative extension.

word-forming element meaning "process of writing or recording" or "a writing, recording, or description" (in modern use especially in forming names of descriptive sciences), from French or German -graphie, from Greek -graphia "description of," used in abstract nouns from graphein "write, express by written characters," earlier "to draw, represent by lines drawn," originally "to scrape, scratch" (on clay tablets with a stylus), from PIE root *gerbh- "to scratch, carve" (see carve).