Classis may refer to:
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Classis (ecclesiastical)
Presbyterian (or presbyteral) polity is a method of church governance ("ecclesiastical polity") typified by the rule of assemblies of presbyters, or elders. Each local church is governed by a body of elected elders usually called the session or ...
, governing body of pastors and elders in certain churches
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Classis (biology)
In biological classification, class ( la, classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. It is a group of related taxonomic orders. Other well-known ranks in descending order of size are life, domain, kingdom ...
, or class, a taxonomic rank or unit in biology
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Classis (port), or Classe, ancient port of Ravenna, Italy
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Roman classis, fleet of Roman navy
{{Disambiguation