Octocoral

Part of speech: noun

Definitions

1. A type of aquatic organism within the cnidarian family that is distinguished by eight tentacles and commonly exists in colonial forms
2. An oceanic life form categorized under cnidarians, recognized for its eight tentacle arrangement and frequent colonial lifestyle
3. A marine creature belonging to the cnidarian group, identified by eight tentacles and typically living in colonies

Etymology: Octocorals are a group of marine animals, mostly soft corals and sea fans, whose polyps have eight feathery tentacles. The name is a back-formation from "Octocorallia", the scientific name of the group, which was built from Greek roots: "okto", meaning eight, and "korallion", meaning coral. Speakers of English then reversed the process, treating the Latinised "Octocorallia" as if it were a compound of "octo-" and "coral" and taking the "-ia" ending off to create a plain English noun. The result is a word that reads as a simple combination of "eight" and "coral", even though it began as the label for a whole taxonomic class. Its parts are straightforward: "octo-" is the familiar prefix for eight, seen in octopus and octagon, and "coral" is the ordinary English word for the hard or soft skeletal animals that build reefs. The word is a technical coinage from the scientific naming of the animals, not an ancient term.