Source : Webster's Revised Unabridged Dictionary (1913)

Obtuse \Ob*tuse"\ a. [Compar. {Obtuser}; superl. {Obtusest}.]
   [L. obtusus, p. p. of obtundere to blunt: cf. F. obtus. See
   {Obtund}.]
   1. Not pointed or acute; blunt; -- applied esp. to angles
      greater than a right angle, or containing more than ninety
      degrees.

   2. Not having acute sensibility or perceptions; dull; stupid;
      as, obtuse senses. --Milton.

   3. Dull; deadened; as, obtuse sound. --Johnson.

Source : WordNet®

obtuse
     adj 1: of an angle; between 90 and 180 degrees [ant: {acute}]
     2: of a leaf shape; rounded at the apex
     3: lacking in insight or discernment; "too obtuse to grasp the
        implications of his behavior"; "a purblind oligarchy that
        flatly refused to see that history was condemning it to
        the dustbin"- Jasper Griffin [syn: {purblind}]
     4: slow to learn or understand; lacking intellectual acuity;
        "so dense he never understands anything I say to him";
        "never met anyone quite so dim"; "although dull at
        classical learning, at mathematics he was uncommonly
        quick"- Thackeray; "dumb officials make some really dumb
        decisions"; "he was either normally stupid or being
        deliberately obtuse"; "worked with the slow students"
        [syn: {dense}, {dim}, {dull}, {dumb}, {slow}]