Eo or EO may refer to:
Eoin Joseph Gerard Morgan (born 10 September 1986) is an Irish-born cricketer who captains the England cricket team in limited overs cricket.
Eobard Thawne, otherwise known as Professor Zoom and the Reverse-Flash, is a supervillain appearing in comic books published by DC Comics.
The Eocene ( ) Epoch, lasting from 56 to 33.9 million years ago, is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era.
EOKA (; Greek: ΕΟΚΑ), acronym for Ethniki Organosis Kyprion Agoniston, was a Greek Cypriot nationalist guerrilla organisation that fought a campaign for the end of British rule in Cyprus, for the island's self-determination and for eventual union with Greece.
Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates.
Eoin Colfer (; born 14 May 1965) is an Irish author of children's books. He worked as a primary school teacher before he became a full-time writer.
Eosinophilic granulomatosis with polyangiitis (EGPA), also known as allergic granulomatosis, is an extremely rare autoimmune condition that causes inflammation of small and medium-sized blood vessels (vasculitis) in persons with a history of airway allergic hypersensitivity (atopy).
Eochaid (fl. 878–889) was a ninth-century Briton who may have ruled as King of Strathclyde and/or King of the Picts.