Oi (also as OI) may refer to:
In biology Grey-faced petrel, also known by its Māori name oi Orthostatic intolerance, a disorder of the autonomic nervous system Osteogenesis imperfecta, a group of genetic bone disorders
In business Oi (telecommunications), the largest landline telephone company in Brazil Organizational intelligence, in business manage
In linguistics Oi (digraph), a Latin-script digraph Oi (interjection), an interjection used to get someone's attention, or to express surprise or disapproval Oi language, a Mon–Khmer dialect cluster of southern Laos Gha, a letter (Ƣ ƣ) erroneously referred to by Unicode as "oi"
In music Oi!, a subgenre of punk rock "Oi!" (song), a 2002 hit song for British grime music crew More Fire Crew
Organisations Oi! (Hong Kong), a visual arts organisation in Hong Kong Oi (Indonesia), an Iwan Fals fanbase foundation in Indonesia Oriental Institute (disambiguation) Orphans International, a global charitable organization that benefits orphans and abandoned children
Other uses Oi (general), Goguryeo general Japanese cruiser Ōi O-I, a Japanese tank design of the Second World War Organoid intelligence, a field of study related to computer science and biology Object Invasion, an American animated webseries from 2016-2020 Object Insanity, an Irish animated webseries from 2014-2018 Operating income
See also Ōi (disambiguation), a number of places in Japan and the name of a light cruiser launched in 1920 Aussie Aussie Aussie, Oi Oi Oi, an Australian chant Oi Oi Oi (album), an album by Boys Noize Oy (disambiguation) Hoy (disambiguation)