# acanthodean

CEFR C2 · Adjective

Source: https://englishreference.com/word/acanthodean
Updated: 2026-05-26

## Definition

relating to a group of ancient fish that lived in the oceans over 400 million years ago. These fish had bony plates and spines on their backs.

For teachers: relating to or characteristic of the Acanthodii, an extinct group of jawed vertebrates that lived during the Paleozoic era. Often used in paleontological and evolutionary biology contexts.

## Examples

- The fossil shows the acanthodean fish's unique spines.
- Scientists studied the acanthodean remains to understand how early jawed fish evolved into modern sharks and rays.
- The discovery of acanthodean fossils in the limestone layers provided critical evidence for the transition from jawless to jawed vertebrates during the Silurian period.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.