The Collaborative International Dictionary of English v.0.48:

Finns \Finns\, n. pl.; sing. Finn. (Ethnol.)
   (a) Natives of Finland; Finlanders.
   (b) A branch of the Mongolian race, inhabiting Northern and
       Eastern Europe, including the Magyars, Bulgarians,
       Permians, Lapps, and Finlanders. [Written also Fins.]
       [1913 Webster]