OOI or Ooi may refer to:
*
Ocean Observatories Initiative
The Ocean Observatories Initiative (OOI) is a National Science Foundation (NSF)br>Major Research Facilitycomposed of a network of science-driven ocean observing platforms and sensors ( ocean observatories) in the Atlantic and Pacific Oceans. Thi ...
, a National Science Foundation Division of Ocean Sciences program
*
Huang (surname)
Huang (; ) is a Chinese surname that originally means and refers to jade people were wearing and decorating in ancient times. While ''Huáng'' is the pinyin romanization of the word, it may also be romanized as Hwang (Korean surname), Hwang, Wong ...
, a Chinese surname
*
Oosterhoff type I
A globular cluster is a spheroidal conglomeration of stars. wikt:globular, Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many mil ...
(OoI), a category of
globular cluster
A globular cluster is a spheroidal conglomeration of stars. Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many millions of membe ...
s
* In Japanese,
ōi is sometimes written as ooi
{{disambiguation