The Collaborative International Dictionary of English v.0.48:

Fro \Fro\ (fr[=o]), adv. [OE. fra, fro, adv. & prep., Icel.
   fr[=a], akin to Dan. fra from, E. from. See From.]
   From; away; back or backward; -- now used only in opposition
   to the word to, in the phrase to and fro, that is, to and
   from. See To and fro under To. --Milton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Fro \Fro\, prep.
   From. [Obs.] --Chaucer.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "fro":
   a rebours, a reculons, against the grain, anticlockwise, arear,
   ass-backwards, astern, away, back, backward, backwards,
   counterclockwise, hindward, hindwards, in reverse, rearward,
   rearwards, retrad, widdershins