Any of several baleen whales of the family Balaenopteridae having longitudinal grooves on the throat and a small, pointed dorsal fin, and including the blue whale and the humpback whale.
[French, from Norwegian rørhval, from Old Norse reydharhvalr : reydhr, rorqual (from raudhr, red; see reudh- in the Appendix of Indo-European roots) + hvalr, whale.]
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