Compulsion; force; duress. It may be either actual, (direct or positive,) where physical force is put upon a man to compel him to do an act against his will, or implied, (legal or constructive,) where the relation of the parties is such that one is under subjection to the other, and is thereby constrained to do what his free will would refuse.
COERCION
TheLaw.com Law Dictionary & Black's Law Dictionary 2nd Ed.