The Collaborative International Dictionary of English v.0.48:

Boorish \Boor"ish\, a.
   Like a boor; clownish; uncultured; unmannerly. --
   Boor"ish*ly, adv. -- Boor"ish*ness, n.
   [1913 Webster]

         Which is in truth a gross and boorish opinion.
                                                  --Milton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

boorish
    adj 1: ill-mannered and coarse and contemptible in behavior or
           appearance; "was boorish and insensitive"; "the loutish
           manners of a bully"; "her stupid oafish husband";
           "aristocratic contempt for the swinish multitude" [syn:
           boorish, loutish, neanderthal, neandertal,
           oafish, swinish]

Moby Thesaurus II by Grady Ward, 1.0:

104 Moby Thesaurus words for "boorish":
   all thumbs, awkward, barbarian, barbaric, blunderheaded,
   blundering, bucolic, bumbling, bungling, butterfingered, caddish,
   careless, carlish, churlish, cloddish, clodhopping, clownish,
   clumsy, clumsy-fisted, coarse, countrified, country-born,
   country-bred, crude, cumbersome, farmerish, fingers all thumbs,
   from the sticks, fumbling, gauche, gawkish, gawky, graceless,
   ham-fisted, ham-handed, hayseed, heavy-handed, hick, hicky,
   hobnailed, hooliganish, hulking, hulky, ill-bred, ill-mannered,
   impolite, inconsiderate, inelegant, insensitive, inurbane,
   left-hand, left-handed, loobyish, loutish, louty, lowbred,
   lubberly, lumbering, lumpen, lumpish, maladroit, nasty, oafish,
   offensive, outlandish, ponderous, provincial, raffish, robustious,
   roughneck, rowdy, rowdyish, rube, rude, ruffianly, rugged, rustic,
   sloppy, stiff, tactless, tasteless, uncivil, uncivilized, uncouth,
   uncultivated, uncultured, unfeminine, ungainly, ungenteel,
   ungentle, ungentlemanly, ungraceful, ungracious, unhandy,
   unladylike, unpoised, unpolished, unrefined, unsolicitous,
   unwieldy, up-country, vulgar, yokel, yokelish