Source : Webster's Revised Unabridged Dictionary (1913)

Buck \Buck\, v. t. [imp. & p. p. {Bucked} (b[u^]kt); p. pr. &
   vb. n. {Bucking}.] [OE. bouken; akin to LG. b["u]ken, Dan.
   byge, Sw. byka, G. bauchen, beuchen; cf. OF. buer. Cf. the
   preceding noun.]
   1. To soak, steep, or boil, in lye or suds; -- a process in
      bleaching.

   2. To wash (clothes) in lye or suds, or, in later usage, by
      beating them on stones in running water.

   3. (Mining) To break up or pulverize, as ores.