black whale

(noun) small dark-colored whale of the Atlantic coast of the United States; the largest male acts as pilot or leader for the school. Synonyms: pilot whale, black whale, common blackfish, blackfish, Globicephala melaena.

(noun) large whale with a large cavity in the head containing spermaceti and oil; also a source of ambergris. Synonyms: sperm whale, cachalot, black whale, Physeter catodon.