poly·​chaete ˈpä-lē-ˌkēt How to pronounce polychaete (audio)
plural polychaetes
: any of a class (Polychaeta) of aquatic and chiefly marine annelid worms (such as clam worms or lugworms) that usually possess paired segmental appendages bearing many bristles, produce free-swimming larvae, and are often brightly colored or bioluminescent : bristle worm
Polychaetes are segmented worms that live in nearly all marine habitats, from the shallow seashore or estuaries to the deep sea. … Many species of these worms—and there are at least 11,500 species worldwide—perform ecological functions similar to those of earthworms, their terrestrial relatives.Carol Simon
They come in every imaginable color and pattern, from completely transparent to iridescent to candy striped. You can find polychaetes of every shape from spherical to sausage-shaped to pencil thin, and every size from microscopic to several feet long.Karen Osborn
polychaete adjective

Examples of polychaete in a Sentence

Recent Examples on the Web The Vanadis Worm: A Marvel of Marine Biology Vanadis bristle worms, also known as polychaetes, live on the Italian island of Ponza, just west of Naples. Paul Smaglik, Discover Magazine, 11 Apr. 2024 The microbes then form the base of the food web in hydrothermal vents and methane seeps, sustaining bigger creatures, including crabs, mussels, and soft-bodied polychaete worms like Pectinereis strickrotti. Laura Baisas, Popular Science, 6 Mar. 2024 Tully has been compared to gastropods (slugs and snails), conodonts (an extinct group of jawless vertebrates), polychaetes (segmented marine worms), nemerteans (ribbon worms), and nectocarids (a squid-like Cambrian organism) in the ensuing decades. Jennifer Ouellette, Ars Technica, 25 Apr. 2023 Diverse animals such as sea mussels, corals, polychaete worms and certain fishes are thought to synchronize their reproductive behavior by the moon. Virat Markandeya, Smithsonian Magazine, 8 Mar. 2023 The anemone that ate the polychaete stayed upright, its body stretched high into the water, for 56 hours after its meal. Elizabeth Preston, Discover Magazine, 7 July 2015 In all likelihood, they were deposited by small, soft-bodied worms—probably an annelid worm like a polychaete—who could have navigated those tight spaces. Jennifer Ouellette, Ars Technica, 5 Feb. 2022 For at least 30 million years, bone-eating worms have been making their homes in the bodies of decomposing whales on the seabottom, but the rotting cetacean carcasses are not just food sources for the polychaetes. Brian Switek, WIRED, 23 Apr. 2010

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'polychaete.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


from the stem of New Latin Polychaeta, class name, neuter plural noun based on Greek polychaítēs "having abundant hair," from poly- poly- + -chaitēs, adjective derivative of chaítē "hair, flowing locks, mane of a horse" — more at chaeta

Note: The taxon Polychaeta was introduced as a modifier—Appendiculata polychaeta "those having appendages with many bristles"—by the German zoologist Adolph Eduard Grube (1812-80) in "Die Familien der Annelida," Archiv für Naturgeschichte, 16. Jahrgang (1850), 1. Band, p. 274. Compare oligochaete.

First Known Use

1891, in the meaning defined above

Time Traveler
The first known use of polychaete was in 1891

Dictionary Entries Near polychaete

Cite this Entry

“Polychaete.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polychaete. Accessed 26 May. 2024.

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