factionary

from The Collaborative International Dictionary of English v.0.48

Factionary \Fac"tion*a*ry\, a. [Cf. F. factionnaire, L.
   factionarius the head of a company of charioteers.]
   Belonging to a faction; being a partisan; taking sides.
   [Obs.]
   [1913 Webster]

         Always factionary on the party of your general. --Shak.
   [1913 Webster]