Source : Webster's Revised Unabridged Dictionary (1913)

Protrusive \Pro*tru"sive\, a.
   1. Thrusting or impelling forward; as, protrusive motion.
      --E. Darwin.

   2. Capable of being protruded; protrusile.

Source : WordNet®

protrusive
     adj : thrusting outward [ant: {intrusive}]