phylum

n. basic subdivision used to classify living things, taxonomic category (Biology)

For other uses, see phyla. In biological taxonomy, a phylum (Greek  plural: phyla) is a taxon in the rank below kingdom and above class. "Phylum" is adopted from the Greek phylai, the clan-based voting groups in Greek city-states. Phyla represent the largest generally accepted groupings of animals and other living things with certain evolutionary traits, although the phyla themselves may sometimes be grouped into superphyla (e.g. Ecdysozoa with eight phyla, including arthropods and roundworms; and Deuterostomia with the echinoderms, chordates, hemichordates and arrow worms). Informally, phyla can be thought of as grouping animals based on general body plan; this is morphological grouping. Thus despite the seemingly different external appearances of organisms, they are classified into phyla based on their internal organizations. For example, though seemingly divergent, spiders and crabs both belong to Arthropoda, whereas earthworms and tapeworms, similar in shape, are from Annelida and Platyhelminthes, respectively. Although the International Code of Botanical Nomenclature allows the use of the term "Phylum" in reference to plants, the term "Division" is almost always used by botanists.
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Noun
1. (linguistics) a large group of languages that are historically related
(hypernym) social group
(classification) linguistics
2. (biology) the major taxonomic group of animals and plants; contains classes
(hypernym) taxonomic group, taxonomic category, taxon
(hyponym) Pyrrophyta, phylum Pyrrophyta
(member-holonym) kingdom
(member-meronym) subphylum
(classification) biology, biological science

n. phylum, basic subdivision used to classify living things, taxonomic category (Biology)

(n.)
One of the larger divisions of the animal kingdom; a branch; a grand division.