'Sibbaldius borealis' definitions:

Definition of 'Sibbaldius borealis'

From: GCIDE

Sulphur-bottom \Sul`phur-bot"tom\, n. (Zool.) A very large whalebone whale of the genus Sibbaldius, having a yellowish belly; especially, Sibbaldius sulfureus of the North Pacific, and Sibbaldius borealis of the North Atlantic; -- called also sulphur whale. [1913 Webster]