The study of the origins of names; onomastics.(noun)
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Use "onomatology" in a sentence
"The interesting and extensive field of personal onomatology -- the study of personal names -- cannot be entered upon exhaustively here."
"Land was to be undertaken solely for the purpose of bringing back living specimens of the five-spotted Arctic woodcock -- _Philohela quinquemaculata_ -- in order to add to our onomatology and our glossary of onomatopoeia an ontogenesis of this important but hitherto unstudied sub-species."
"In order to understand the onomatology question in medicine as it stands at present one has to read this book."