Same an in humans... The spine.
However, you questions says 'ON A FISH' so you may be thinking of the fin on a shark?
In that case it is called the dorsal fin.
Another name for devils backbone is Backbone Mountain.
another name for backbone is vertebrae column
The spine.
vertabre
yes fish have a backbone
your spine
vertebrate
It is a backbone.
All fish have a backbone and a skull.
a fish with a backbone
No it is a vertebrate. Fish have a backbone. Invertebrates do not have a backbone.
Another name for a flying fish is a Ray-Finned fish.