Relating to whales or more generally to any marine mammal of the order Cetacea.(adjective)
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Use "cetaceous" in a sentence
"I am staying at the home of a friend who is a great admirer of Moby Dick and whose home is replete with cetaceous memorabilia."
"If we suppose the case of the discovery of a skeleton of a Greenland whale in a fossil state, not a single cetaceous animal being known to exist, what naturalist would have ventured conjecture on the possibility of a carcass so gigantic being supported on the minute crustacea and mollusca living in the frozen seas of the extreme North?"
"Lang Ca Ong, the Temple of the Whales, was built in 1911 and had about it a distinctly non-Buddhist air, with its cases of cetaceous skeletons."