reducible

adjective
  1. 1

    Capable of being reduced.

  2. 2

    (of a polynomial) Able to be factored into polynomials of lower degree, as x^2-1.

  3. 3

    (of an integer) Able to be factored into smaller integers; composite.

  4. 4

    (of a manifold) Containing a sphere of codimension 1 that is not the boundary of a ball.

Source: https://en.wiktionary.org/wiki/reducible