Long imprisonment and hard constraint. --Spenser.
Not by constraint, but by my choice, I came. --Dryden.
Syn: Compulsion; violence; necessity; urgency.
Usage: {Constraint}, {Compulsion}. Constraint implies strong
binding force; as, the constraint of necessity; the
constraint of fear. Compulsion implies the exertion of
some urgent impelling force; as, driven by compulsion.
The former prevents us from acting agreeably to our
wishes; the latter forces us to act contrary to our
will. Compulsion is always produced by some active
agent; a constraint may be laid upon us by the forms
of civil society, or by other outward circumstances.
--Crabb.