class Echinoidea

9.6

A group of sea animals like sea urchins and sand dollars with spines and body parts arranged around the center

noun
/klæs ˌɛkɪˈnɔɪdɪə/

Specialized

: clase Echinoidea

The class Echinoidea is known for its distinctive spiny shells and includes sea urchins and sand dollars.

Examples

The class Echinoidea contains both sea urchins and sand dollars, diverse in form and habitat.
Marine biologists study the evolutionary adaptations of the class Echinoidea to understand their role in ocean ecosystems.
Fossils from the class Echinoidea provide valuable insights into ancient marine environments.
The class Echinoidea includes various species of sea urchins.
Many marine biologists study the class Echinoidea for their unique adaptations.
Research on the class Echinoidea has revealed important information about marine biodiversity and ecosystems.
Many species in the class Echinoidea play a vital role in their habitats, contributing to the health of ocean environments.

Synonyms

Echinoidea

vsclass Echinoidea

Specialized

9.9

A group of sea animals with hard, spiny shells like sea urchins and sand dollars

focuses on radial symmetry rather than shell hardness

Surface Forms

class Echinoidea singular

classes Echinoidea plural

Morphology

class + Echinoidea

The phrase is fully compositional: 'class' (a category) combined with the taxon name 'Echinoidea' denotes the taxonomic group containing sea urchins, a meaning directly derivable from the constituents. This label-formation pattern (category word + scientific name) is cross-linguistically regular and predictable for learners who know both words.

Etymology

Class Echinoidea comes from Greek: echinos means 'hedgehog' because these animals are covered in spines, and -oidea means 'like'. So the name literally says 'hedgehog-like' and helps you remember this class is the group of 'spiny' sea animals such as sea urchins and sand dollars.