Knife-edge

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Knife-edge \Knife"-edge`\, n. (Mech.)
     A piece of steel sharpened to an acute edge or angle, and
     resting on a smooth surface, serving as the axis of motion of
     a pendulum, scale beam, or other piece required to oscillate
     with the least possible friction.
     [1913 Webster]


  
     {Knife-edge file}. See Illust. of {File}.
        [1913 Webster]

From WordNet (r) 2.0 [wn]:

  knife-edge
       n : a narrow boundary; "he lived on a knife-edge between genius
           and insanity"