![thornback thornback](https://www.tekportal.net/wp-content/uploads/2018/11/thornback.jpg)
noun
- a skate, Raja clavata, of European waters, having short spines on the back and tail.
- a California ray, Platyrhinoidis triseriatus, belonging to the guitarfish group.
noun
- a European ray, Raja clavata, having a row of spines along the back and tail
- a similar fish, Platyrhinoidis triseriata, of the Pacific Ocean