One who defines and explains terms; one versed in glossology.(noun)
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Use "glossologist" in a sentence
"But the eventual success of linguist over glossologist would not have been easily predicted by one scanning the OED, for the only sense current for linguist was ` one who is skilled in the use of language, master of other tongues besides his own, 'the sense in which Shakespeare used it at the end of the 16th century."