WordNet (r) 3.0 (2006):

beat down
    v 1: persuade the seller to accept a lower price; "She beat the
         merchant down $100" [syn: beat down, bargain down]
    2: shine hard; "The sun beat down on the hikers"
    3: dislodge from a position; "She beat the dealer down to a much
       better price"

Moby Thesaurus II by Grady Ward, 1.0:

134 Moby Thesaurus words for "beat down":
   bargain, bear down, bend, bid, bid for, blow down, break,
   break down, bring down, bring low, bring to terms, browbeat,
   bulldoze, bully, burn down, cast down, castrate, chaffer, cheapen,
   chop down, clamp down on, coerce, compel, conquer, cow, crush, cut,
   cut down, cut prices, damp, dampen, dampen the spirits, darken,
   dash, daunt, decline, defeat, deflate, deject, depreciate, depress,
   despotize, devaluate, dicker, discourage, dishearten, dispirit,
   dive, domineer, domineer over, drive a bargain, enslave, fall,
   fall in price, fell, flatten, give way, grind, grind down, haggle,
   henpeck, higgle, huckster, humble, humiliate, intimidate, jew down,
   keep down, keep under, knock down, knock over, level, lord it over,
   lower, lower the spirits, mark down, master, mow down, negotiate,
   nose-dive, oppress, outbid, overawe, overbear, overmaster,
   overpower, override, overwhelm, pare, plummet, plunge, press down,
   press heavy on, prostrate, pull down, quell, rase, raze, reduce,
   repress, ride over, ride roughshod over, sadden, sag, shave, sink,
   slash, slump, smash, steamroller, subdue, subjugate, suppress,
   take down, tear down, terrorize, throw down, trample down,
   trample underfoot, trample upon, tread down, tread underfoot,
   tread upon, trim, tyrannize, tyrannize over, underbid, unman,
   vanquish, walk all over, walk over, weigh heavy on,
   weigh heavy upon, weigh upon