ˈ ̷ ̷ˌ ̷ ̷ noun
Etymology: whale (I) + back
1. : something (as a hill or wave) shaped like the back of a whale
2.
a. : turtleback c
b. : a steamship having sides curving in towards the ends, a spoon bow, and a very convex upper deck formerly used (as for carrying grain or ore) on the Great Lakes