Source : Webster's Revised Unabridged Dictionary (1913)

Bestride \Be*stride"\, v. t. [imp. {Bestrode}, (Obs. or R.)
   {Bestrid}; p. p. {Bestridden}, {Bestrid}, {Bestrode}; p. pr.
   & vb. n. {Bestriding}.] [AS. bestr[=i]dan; pref. be- +
   str[=i]dan to stride.]
   1. To stand or sit with anything between the legs, or with
      the legs astride; to stand over

            That horse that thou so often hast bestrid. --Shak.

            Why, man, he doth bestride the narrow world Like a
            Colossus.                             --Shak.

   2. To step over; to stride over or across; as, to bestride a
      threshold.

Source : WordNet®

bestride
     v : get on the back of; "mount a horse" [syn: {hop on}, {mount},
          {mount up}, {get on}, {jump on}, {climb on}] [ant: {hop
         out}]
     [also: {bestrode}, {bestridden}, {bestrid}]