noun

A segmented worm of the phylum Annelida, such as an earthworm or leech.

Most biologists are familiar with only a few of the approximately 40 extant animal phyla such as annelids, arthropods, molluscs, echinoderms and chordates.

adjective

Relating to or denoting annelids.

These differences in expression domains indicate changes in the regulation of these genes somewhere in the annelid lineage.