forestaller

Etymology
From, , , equivalent to.

Noun

 * : one who, or that which, forestalls.
 * 1)  One who preemptively purchases goods in order to drive up their market price for resale.
 * 2)  A device that overrides an automatic brake signal.
 * 3)  One who obstructs a road, especially in order to intercept traffic.
 * 1)  One who obstructs a road, especially in order to intercept traffic.