annelid

EN
noun

🇺🇸

/ˈænəlɪd/

🇺🇸

/ˈænəlɪd/

🇬🇧

/ˈænəlɪd/

🇬🇧

/ˈænəlɪd/

Word Forms

Plural

annelids

Description

Annelid is a scientific noun referring to a large group of invertebrate animals—like earthworms, leeches, and marine fan worms—that have long, soft, segmented bodies resembling a chain of rings. They’re ecologically vital: earthworms aerate soil, while polychaetes filter-feed in oceans and serve as food for fish.

Examples

The common earthworm is a terrestrial annelid that improves soil health.

Divers often spot colorful polychaete annelids waving their feathery tentacles in coral reef currents.

Unlike flatworms, annelids possess a true coelom—a fluid-filled body cavity that houses complex organs.

Leeches, once used in medieval medicine, are blood-feeding annelids with specialized suckers.

Scientists study annelid regeneration to understand how some species regrow entire body segments after injury.

Root

annel

Comes from the Latin word 'anellus', a diminutive of 'anulus' meaning 'ring'. It refers to the segmented, ring-like body structure characteristic of this phylum. Examples include annelid, annelated, annulation, annular.

id

A Greek-derived suffix (from '-eides') meaning 'resembling' or 'having the form of'; commonly used in biological taxonomy to denote a class or group (e.g., arachnid, echinoid, crustaceid). In 'annelid', it signifies 'ring-shaped (organism)'.