whaleback

noun

(historical) A kind of cargo steamship with a hull that continuously curves above the waterline from vertical to horizontal.

The whaleback ship was a unique design with a rounded hull.

意味（1）

(historical) A kind of cargo steamship with a hull that continuously curves above the waterline from vertical to horizontal.

意味（2）

(geology) A landform (typically a sand dune) having the form of the back of a whale.