(biology) Any species that has been introduced to an environment where it is not native, and that has since become a nuisance through rapid spread and increase in numbers, often to the detriment of native species.

(taxonomy) A scientific name at the rank of species, with two terms: the generic name (or generic epithet, the genus of the species) and the specific name (a term used only in zoology, never in botany, for the second part of a binomial) or the specific epithet (the term always used in botany, which can also be used in zoology).

(taxonomy) A species which has been designated as typical of a genus, and is chosen as the species according to which the genus is named.

(taxonomy) A grouping of closely-related species that are treated like a single species for practical purposes.

(ecology) Any species of organism that is vulnerable to extinction in the near future

(ecology) A species that exerts a large, stabilizing influence throughout an ecological community, despite its relatively small numerical abundance.

(chemistry) An ensemble of chemically identical molecular entities that can explore the same set of molecular energy levels on the time scale of the experiment.

A subgrouping of standard cloud classification system, coming after the major cloud genera

plural of species name

Synonym of specific epithet