- a cargo vessel having a hull with a convex deck.
- a deck or cover curving upward.
Examples from the Web for whaleback
I can't make out what they are on; but it looks like a whaleback to me, with her upper works carried away.Across India|Oliver Optic
With ample artillery and fresh reserves at our command we were determined to gain the summit of the whaleback in a final drive.
An artistic illustration is given of the "whaleback" steamer, used principally on our Northern lakes.My Native Land|James Cox
In the centre it rose to probably six feet and then fell very gradually, whaleback fashion, to the south.Over Prairie Trails|Frederick Philip Grove
He went by the Suburban, because he wanted to go over to the avenues, and Cowles went down by the Whaleback.'Against Odds|Lawrence L. Lynch