A person who studies molluscs, who specializes in malacology.(noun)
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Use "malacologist" in a sentence
"Of course, not every malacologist is expected to go to the AMS meetings."
"Call yourself a malacologist and you can't name a slug horror film."
"Earlier today, while looking up some papers in The Nautilus from 1971, I chanced upon a short article by the late malacologist Dee Dundee titled United States research trends in malacology (85: 67-69; pdf of vol 85)."