Hexacoral

Part of speech: noun

Definitions

1. Any marine animal of the subclass Hexacorallia, such as a stony coral or sea anemone, whose polyp tentacles come in multiples of six
2. A sea anemone or stony coral belonging to the group of anthozoans whose polyps have six-fold symmetry and tentacles in sets of six
3. An anthozoan polyp from the subclass of corals and anemones that is characterized by six-part body symmetry and tentacles arranged in multiples of six

Etymology: Hexacoral is a zoological term for any member of the anthozoan group whose polyps have six-fold symmetry, such as sea anemones and stony corals. Its name is built from the Greek prefix "hex-", meaning six, joined to the ordinary English word "coral." The Latin-derived "Hexacorallia" was formed from the same two elements, and the English term is a partial calque of that scientific name, meaning it copies the Latin structure while keeping the English "coral" in place of the Latin "corallium." The surprising part is how literally the name describes the animals. The sea anemones and corals grouped here have tentacles and internal partitions in multiples of six, a feature that separates them from the octocorals, which are built on eight. The word therefore names a body plan rather than a colour or habitat, and the "six" in it is a counted structural feature that taxonomists could check under a microscope.