from
The Collaborative International Dictionary of English v.0.48
Rorqual \Ror"qual\, n. [Norw. rorqualus a whale with folds.]
(Zool.)
A very large North Atlantic whalebone whale ({Physalus
antiquorum}, or {Balaenoptera physalus}). It has a dorsal
fin, and strong longitudinal folds on the throat and belly.
Called also {razorback}.
[1913 Webster]
Note: It is one of the largest of the whales, somethimes
becoming nearly one hundred feet long, but it is more
slender than the right whales, and is noted for its
swiftness. The name is sometimes applied to other
related species of finback whales.
[1913 Webster]