If someone asks you what you have in common with the Antarctic icefish, you can say that you both belong to the same phylum, meaning the same taxonomic group: you are both vertebrates.

Biology types are probably already familiar with using the word phylum as a way to classify animals and plants. Mammals, including humans, are part of the phylum chordata, which also includes fishes, amphibians, reptiles, and birds. As you can see that’s a very broad category. Phylum comes above class and below kingdom in the biological classification system. The ranks get increasingly narrow, working all the way down to species, which is a closely related group.

Definitions of phylum

n (biology) the major taxonomic group of animals and plants; contains classes

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Pyrrophyta, phylum Pyrrophyta
a division of lower plants comprising unicellular and biflagellate algae that form starchy compounds
Protozoa, phylum Protozoa
in some classifications considered a superphylum or a subkingdom; comprises flagellates; ciliates; sporozoans; amoebas; foraminifers
Cryptophyta, phylum Cryptophyta
a phylum in the kingdom Protoctista
Chordata, phylum Chordata
comprises true vertebrates and animals having a notochord
Cephalochordata, subphylum Cephalochordata
Tunicata, Urochorda, Urochordata, subphylum Tunicata, subphylum Urochorda, subphylum Urochordata
Craniata, Vertebrata, subphylum Craniata, subphylum Vertebrata
fishes; amphibians; reptiles; birds; mammals
Arthropoda, phylum Arthropoda
jointed-foot invertebrates: arachnids; crustaceans; insects; millipedes; centipedes
Pentastomida, subphylum Pentastomida
tongue worms
Porifera, phylum Porifera
coextensive with the subkingdom Parazoa: sponges
Cnidaria, Coelenterata, phylum Cnidaria, phylum Coelenterata
hydras; polyps; jellyfishes; sea anemones; corals
Ctenophora, phylum Ctenophora
comb jellies; sea acorns; a small phylum formerly considered a class of Coelenterata
Acanthocephala, phylum Acanthocephala
phylum or class of elongated wormlike parasites that live in the intestines of vertebrates: spiny-headed worms
Chaetognatha, phylum Chaetognatha
arrowworms: a group of small active transparent marine worms
Platyhelminthes, phylum Platyhelminthes
Nemertea, Nemertina, phylum Nemertea, phylum Nemertina
proboscis worms
Pogonophora, phylum Pogonophora
beard worms
Rotifera, phylum Rotifera
a phylum including: rotifers
Aschelminthes, Nematoda, phylum Aschelminthes, phylum Nematoda
unsegmented worms: roundworms; threadworms; eelworms
Annelida, phylum Annelida
segmented worms: earthworms; lugworms; leeches
Mollusca, phylum Mollusca
gastropods; bivalves; cephalopods; chitons
Phoronida, Phoronidea, phylum Phoronida
small phylum of wormlike marine animals
Bryozoa, phylum Bryozoa, polyzoa
marine or freshwater animals that form colonies of zooids
Ectoprocta, phylum Ectoprocta
coextensive with or a subphylum of Bryozoa
Endoprocta, Entoprocta, phylum Entoprocta
sometimes considered a subphylum of Bryozoa
Cycliophora, phylum Cycliophora
tiny marine organisms each the size of a period found in great numbers on lobsters' lips; identified tentatively in 1995 as a new phylum or as possible link between Entoprocta and Ectoprocta
Brachiopoda, phylum Brachiopoda
marine invertebrates that resemble mollusks
Sipuncula, phylum Sipuncula
peanut worms
Echinodermata, phylum Echinodermata
radially symmetrical marine invertebrates including e.g. starfish and sea urchins and sea cucumbers
(botany) taxonomic unit of plants corresponding to a phylum
Protista, division Protista
eukaryotic one-celled living organisms distinct from multicellular plants and animals: protozoa, slime molds, and eukaryotic algae
used only in former classifications: comprising what is now considered a heterogeneous assemblage of flowerless and seedless organisms: algae; bacteria; fungi; lichens
Tracheophyta, division Tracheophyta
in former classifications: comprising plants with a vascular system including ferns and fern allies as well as seed plants
Bryophyta, division Bryophyta
a division of nonflowering plants characterized by rhizoids rather than true roots and having little or no organized vascular tissue and showing alternation of generations between gamete-bearing forms and spore-bearing forms; comprises true mosses (Bryopsida) and liverworts (Hepaticopsida) and hornworts (Anthoceropsida)
Pteridophyta, division Pteridophyta
containing all the vascular plants that do not bear seeds: ferns, horsetails, club mosses, and whisk ferns; in some classifications considered a subdivision of Tracheophyta
Spermatophyta, division Spermatophyta
seed plants; comprises the Angiospermae (or Magnoliophyta) and Gymnospermae (or Gymnospermophyta); in some classification systems Spermatophyta is coordinate with Pteridophyta (spore producing plants having vascular tissue and roots) and Bryophyta (spore producing plants lacking vascular tissue and roots)
in former classification systems: one of two major plant divisions, including all seed-bearing plants; superseded by the division Spermatophyta
in former classification systems: one of two major plant divisions, including all plants that do not bear seeds: ferns, mosses, algae, fungi
Pteropsida, subdivision Pteropsida
used in former classifications to include all ferns and flowering plants and divided into the three classes Filicinae and Gymnospermae and Angiospermae
Zygomycota, Zygomycotina, subdivision Zygomycota, subdivision Zygomycotina
division of fungi having sexually produced zygospores
Gymnomycota, Myxomycota, division Gymnomycota, division Myxomycota
slime molds; organisms having a noncellular and multinucleate creeping vegetative phase and a propagative spore-producing stage: comprises Myxomycetes and Acrasiomycetes; in some classifications placed in the kingdom Protoctista
Mastigomycota, Mastigomycotina, subdivision Mastigomycota, subdivision Mastigomycotina
fungi in which the spores and gametes are motile; in some systems placed in the Phycomycetes group with the Zygomycota
Lichenes, division Lichenes
comprising the lichens which grow symbiotically with algae; sometimes treated as an independent group more or less coordinate with algae and fungi
Eumycota, division Eumycota
true fungi; eukaryotic heterotrophic walled organisms; distinguished from Myxomycota (funguslike slime molds): comprises subdivisions Mastigomycotina; Zygomycotina; Ascomycotina; Basidiomycotina; Deuteromycotina (imperfect fungi)
Deuteromycota, Deuteromycotina, Fungi imperfecti, subdivision Deuteromycota, subdivision Deuteromycotina
large and heterogeneous form division of fungi comprising forms for which no sexually reproductive stage is known
Basidiomycota, Basidiomycotina, subdivision Basidiomycota, subdivision Basidiomycotina
comprises fungi bearing the spores on a basidium; includes Gasteromycetes (puffballs) and Tiliomycetes comprising the orders Ustilaginales (smuts) and Uredinales (rusts) and Hymenomycetes (mushrooms, toadstools, agarics and bracket fungi); in some classification systems considered a division of kingdom Fungi
Ascomycota, Ascomycotina, subdivision Ascomycota, subdivision Ascomycotina
a large subdivision of Eumycota including Hemiascomycetes and Plectomycetes and Pyrenomycetes and Discomycetes; sac fungi; in some classification systems considered a division of the kingdom Fungi
used in some classifications for the class Lycopsida: club mosses
Type of:
taxon, taxonomic category, taxonomic group
animal or plant group having natural relations

n (linguistics) a large group of languages that are historically related

Type of:
social group
people sharing some social relation

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