Convertible /(?)/

Con·vert·i·ble

Convertible

a.
  1. Capable of being converted; susceptible of change; transmutable; transformable.
    Minerals are not convertible into another species, though of the same genus.
    — Harvey.
  2. Capable of being exchanged or interchanged; reciprocal; interchangeable.
    So long as we are in the regions of nature, miraculous and improbable, miraculous and incredible, may be allowed to remain convertible terms.