The Collaborative International Dictionary of English v.0.48:

Browbeat \Brow"beat`\, v. t. [imp. Browbeat; p. p.
   Browbeaten; p. pr. & vb. n. Browbeating.]
   To depress or bear down with haughty, stern looks, or with
   arrogant speech and dogmatic assertions; to abash or
   disconcert by impudent or abusive words or looks; to bully;
   as, to browbeat witnesses.
   [1913 Webster]

         My grandfather was not a man to be browbeaten. --W.
                                                  Irving.
   [1913 Webster]

WordNet (r) 3.0 (2006):

browbeat
    v 1: be bossy towards; "Her big brother always bullied her when
         she was young" [syn: strong-arm, bully, browbeat,
         bullyrag, ballyrag, boss around, hector, push
         around]
    2: discourage or frighten with threats or a domineering manner;
       intimidate [syn: browbeat, bully, swagger]

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "browbeat":
   badger, beat down, bludgeon, bluster, bluster out of, bounce,
   break, bulldoze, bully, bullyrag, castrate, clamp down on, coerce,
   compel, cow, daunt, demoralize, despotize, discourage, dominate,
   domineer, domineer over, dragoon, enslave, frighten, grind,
   grind down, harass, hassle, hector, henpeck, huff, intimidate,
   keep down, keep under, lord it over, nag, oppress, overawe,
   overbear, overmaster, override, press heavy on, repress, ride over,
   ride roughshod over, subjugate, suppress, systematically terrorize,
   terrorize, threaten, trample down, trample upon, tread down,
   tread upon, tyrannize, tyrannize over, unman, walk all over,
   walk over, weigh heavy on