N opponent, antagonist, adversary, adverse party, opposition, enemy, the other side, assailant, oppositionist, obstructive, brawler, wrangler, brangler, disputant, filibuster, obstructionist, malcontent, Jacobin, Fenian, demagogue, reactionist, rival, competitor, bete noir.

Recoil

N recoil, reaction, retroaction, revulsion, bounce, rebound, ricochet, repercussion, recalcitration, kick, contrecoup, springing back, elasticity, reflection, reflexion, reflex, reflux, reverberation, rebuff, repulse, return, ducks and drakes, boomerang, spring, reactionist, elastic collision, coefficient of restitution, recoiling, refluent, repercussive, recalcitrant, reactionary, retroactive, on the rebound, on the recoil, for every action there is a reaction, equal in force and opposite in direction.

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