An expert in ichthyology: one who studies fishes.(noun)
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Use "ichthyologist" in a sentence
""They're nutty people," says ichthyologist Robert Behnke , a retired Colorado State University professor and expert on North American trout who calls the bug advocates "obstructionists.""
"That appears to be correct *I am not even close to being either a paleontologist or an ichthyologist*."
"Christiana, our ichthyologist managed to net two beautiful and exotic frog fish, normally coastal species, hanging around."