Mythical creatures that are human from the waist up and fish from the waist down.(noun)
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Use "merfolk" in a sentence
"Tori Truslow's scholarly "Tomorrow Is Saint Valentine's Day" tells the story of the Great Ice Train and its encounter with the merfolk on the Moon."
"The merfolk of the Harbor comb candy wrappers from their hair, but keep the beer bottles for elaborate art installations, fashion jewelry from pull-tabs"
"But it turned out to be an unexpected joy right from the first page: richly and sensually written, it mines deep seams of imagination and characterisation in its portrayal of an alternate world in which land-dwelling humans share medieval Europe with merfolk-like 'deepsmen'."