The Collaborative International Dictionary of English v.0.48:

Pointless \Point"less\, a.
   Having no point; blunt; wanting keenness; obtuse; as, a
   pointless sword; a pointless remark.
   [1913 Webster]

   Syn: Blunt; obtuse, dull; stupid.
        [1913 Webster]

WordNet (r) 3.0 (2006):

pointless
    adj 1: not having a point especially a sharp point; "my pencils
           are all pointless" [syn: pointless, unpointed] [ant:
           pointed]
    2: serving no useful purpose; having no excuse for being;
       "otiose lines in a play"; "advice is wasted words"; "a
       pointless remark"; "a life essentially purposeless";
       "senseless violence" [syn: otiose, pointless,
       purposeless, senseless, superfluous, wasted]

Moby Thesaurus II by Grady Ward, 1.0:

103 Moby Thesaurus words for "pointless":
   abrupt, absurd, aimless, arid, asinine, barren, blah, blank,
   bloodless, bluff, blunt, blunt-edged, blunt-ended, blunt-pointed,
   blunted, bluntish, bootless, characterless, cold, colorless, dead,
   dismal, draggy, drearisome, dreary, dry, dryasdust, dull,
   dull-edged, dull-pointed, dulled, dullish, dusty, edgeless, effete,
   elephantine, empty, etiolated, fade, faired, fatuous, feckless,
   flat, fruitless, futile, heavy, ho-hum, hollow, impotent, inane,
   ineffective, ineffectual, inexcitable, insignificant, insipid,
   jejune, leaden, lifeless, low-spirited, meaningless, no go,
   nonsensical, obtuse, of no use, pale, pallid, pedestrian, plodding,
   poky, ponderous, preposterous, purportless, purposeless,
   ridiculous, rounded, senseless, silly, slow, smoothed, solemn,
   spiritless, sterile, stiff, stodgy, stuffy, stupid, superficial,
   superfluous, tasteless, tedious, unavailing, unedged, unlively,
   unmeaning, unpointed, unproductive, unsharp, unsharpened, useless,
   vain, vapid, wooden, worthless