This if from Anime Colony (http://www.scifi.com/anime/)
OAV (original animated video)
OVA (original video animation)
n. An anime program that was not shown on television, nor shown in theaters, but was released directly to the Japanese home video market. Common form for releasing adult anime product, as well as mainstream anime product until 1998, when mainstream product started moving to late night and satellite TV stations. OAV's typically run 30 minutes to an hour, but can be as long as a feature movie. Often released in multi-part series.
