A category used in the classification of organisms that consists of one or several similar or closely related classes. Examples of phyla are the Ascomycota, Bryophyta, and Chordata. In traditional classification schemes phyla are grouped into kingdoms, and for plants the division is sometimes used instead of the phylum.
Geology and Earth Sciences
In animal taxonomy, one of the major groupings, coming below subkingdom and kingdom, and comprising superclasses, classes, and all lower taxa.
Geography
The second highest category (of seven) in the scientific system of classification for organisms (pl. phyla), consisting of one or several similar or closely related classes. Hence, phylogeography, the study of the historical processes that may be responsible for the contemporary geographic distributions of individuals. This is accomplished by considering the geographic distribution of individuals in the light of the patterns associated with a gene genealogy; J. Avise (2000).