WordNet (r) 3.0 (2006):

hem in
    v 1: surround in a restrictive manner; "The building was hemmed
         in by flowers"
    2: surround so as to force to give up; "The Turks besieged
       Vienna" [syn: besiege, beleaguer, surround, hem in,
       circumvent]

Moby Thesaurus II by Grady Ward, 1.0:

83 Moby Thesaurus words for "hem in":
   beleaguer, beset, besiege, blockade, bottle up, bound, box, box in,
   box up, cage, chamber, check, circumscribe, cloister, close in,
   compass, confine, constrain, contain, coop, coop in, coop up,
   cordon, cordon off, cork up, corral, cramp, crib, detain, encage,
   encircle, enclose, encompass, enshrine, fence in, hedge in, hem,
   hold, hold in custody, hold in restraint, house in, immure,
   impound, imprison, incarcerate, include, inhibit, jail,
   keep from spreading, keep in, keep in custody, keep in detention,
   keep within bounds, kennel, leaguer, limit, localize, mew, mew up,
   narrow, pen, pen in, pen up, pocket, pound, qualify, quarantine,
   rail in, restrain, restrict, seal up, shackle, shrine, shut in,
   shut up, stable, stint, surround, tighten, wall in, wrap, yard,
   yard up