Compulsion

Com*pul"sion (?), n. [L. compulsio. See Compel.] The act of compelling, or the state of being compelled; the act of driving or urging by force or by physical or moral constraint; subjection to force.

If reasons were as plentiful as blackberries, I would give no man a reason upon compulsion.
Shak.

With what compulsion and laborious flight
We sunk thus low.
Milton.

Syn. -- See Constraint.