The Collaborative International Dictionary of English v.0.48:

Semicubical \Sem`i*cu"bic*al\, a. (Math.)
   Of or pertaining to the square root of the cube of a
   quantity.
   [1913 Webster]

   Semicubical parabola, a curve in which the ordinates are
      proportional to the square roots of the cubes of the
      abscissas.
      [1913 Webster] Semicubium