Dictionary Definition :
Definition[1]
:
The nine kinds of, and meditations on, 無爲 q.v. There are two somewhat different groups; one has 擇滅, 非擇滅, 虛空, 空無邊處, 識無邊處, 無所有處, 非想非非想處 (v. 九有情處), 緣起支性, and 聖道支性.
Source
:
A Dictionary of Chinese Buddhist Terms, William Edward Soothill and Lewis Hodous