What does bryozoan mean?
A bryozoan is a minute aquatic invertebrate belonging to the phylum Bryozoa, a group popularly known as "moss animals" because many colonies form mossy or lacy encrustations on underwater surfaces. Although each individual, called a zooid, is barely visible to the naked eye, bryozoans live together in colonies that can blanket rocks, shells, kelp, and even ship hulls with intricate calcified or gelatinous structures. Nearly all species are marine, though a few inhabit fresh water. Using a crown of ciliated tentacles known as a lophophore, each zooid filters microscopic food particles from the water. Bryozoans are important both ecologically, as reef and seabed builders, and geologically: their abundant skeletons make them common fossils, tracing back hundreds of millions of years.
nounA minute aquatic invertebrate of the phylum Bryozoa, forming colonies of tiny individuals (zooids) that typically encrust rocks, shells, and seaweeds; also called a moss animal.
- Any member of the phylum Bryozoa: a small colonial aquatic invertebrate whose individuals (zooids) secrete protective skeletons and feed using a ciliated lophophore.
"Under the microscope, the bryozoan's colony revealed an intricate lattice of boxlike zooids."
"Divers found delicate lace-like bryozoans carpeting the pilings of the old pier."
"The limestone was packed with fossil bryozoans, evidence that the region lay beneath a shallow sea millions of years ago."
The regular English plural is "bryozoans" for individual animals; the capitalized Latin form "Bryozoa" denotes the phylum as a whole and functions as a plural collective noun.
"Fossil bryozoans are among the most abundant remains in Paleozoic marine sediments."
Some bryozoan colonies are essentially immortal — individual zooids die off, but the colony can keep growing for thousands of years, making them among the longest-lived animals on Earth.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of bryozoan
The word "bryozoan" derives from New Latin Bryozoa, coined in the 19th century by combining two Ancient Greek roots: "bryon," meaning moss, and "zōion," meaning animal — literally "moss animal." The same Greek root "bryon" appears in "bryology," the study of mosses, and in "bryophyte," the botanical group comprising mosses and liverworts, while "zōion" survives in words like "protozoan."
Related word forms
How bryozoan is actually used
"Bryozoan" is chiefly a scientific and natural-history term; in everyday speech these animals are more often described informally as "moss animals" or "sea mats." The plural "Bryozoa" (capitalized) refers to the phylum itself, while lowercase "bryozoans" is the normal plural for individual animals.
Easily confused with bryozoan
Corals are cnidarians related to sea anemones, whereas bryozoans are lophophorate invertebrates with a completely different body plan.
A bryophyte is a land plant such as a moss or liverwort, while a bryozoan is an aquatic colonial animal — the names both derive from Greek 'bryon' (moss).