ol·i·gop·o·ly 
(ŏl′ĭ-gŏpə-lē, ō′lĭ-)
(ŏl′ĭ-gŏpə-lē, ō′lĭ-)n. pl. ol·i·gop·o·lies
A market condition in which sellers are so few that the actions of any one of them will materially affect price and have a measurable impact on competitors.
[OLIGO- + (MONO)POLY.]
ol′i·gop′o·listic (-lĭstĭk) adj.