Definitions

1. noun

A smallmouth bass with a quill-like growth on its back, or a type of catfish with a distinctive quill-like growth on its back.

“The quillback is a popular game fish in North American rivers and streams.”

2. noun

Any of several species of catfish, especially in the genus Carpiodes, that have a quill-like growth on their back.

“The quillback catfish is found in the Mississippi River basin.”