Urochordates

Part of speech: noun

Definitions

1. A clade of marine organisms exhibiting a notochord during their larval phase, primarily represented by sea squirts, which belongs to the phylum Chordata and shows distinctive tubular shapes
2. This category comprises aquatic creatures recognized for having a supportive notochord in their juvenile forms, often associated with filter-feeding habits and includes species like sea squirts
3. A group of sea-dwelling animals characterized by possessing a flexible rod for structural support in their early development, mainly composed of sea squirts

Etymology: Urochordates are a group of marine animals whose name is built from Greek roots: "oura" (tail) and "chorde" (cord), with the "-ate" ending marking a member of the group. The name describes the notochord, the flexible rod that gives the larval tail its support. Adult sea squirts lose the tail and most of this structure, but the larvae keep it, which is why the name points to the tail rather than to the adult form. Because the name refers to a feature seen in the young animal, it is a scientific coinage built from classical parts rather than a word that Greek speakers used for these creatures. Scientists applied the label to the whole group, which includes the sea squirts and related filter feeders.