/greg"euh ruyn', -euhr in/ , n.
1. a type of sporozoan parasite that inhabits the digestive and other cavities of various invertebrates and produces cysts filled with spores.
adj.
2. having the characteristics of or pertaining to a gregarine or gregarines.
[ 1865-70; Gregarina name of type, equiv. to L gregar ( ius ) (see GREGARIOUS) + -ina -INE 1 ]