Coerce, v. t. [imp. & p. p. Coerced; p. pr. & vb. n. Coercing.]
Etymology: [L. coërcere; co- + arcere to shut up, to press together. See Ark.]
1. To restrain by force, especially by law or authority; to repress; to curb. Burke. Punishments are manifold, that they may coerce this profligate sort. Ayliffe.
2. To compel or constrain to any action; as, to coerce a man to vote for a certain candidate.
3. To compel or enforce; as, to coerce obedience.
Syn. -- To Coerce, Compel. To compel denotes to urge on by force which cannot be resisted. The term aplies equally to physical and moral force; as, compelled by hunger; compelled adverse circumstances; compelled by parental affection. Coerce had at first only the negative sense of checking or restraining by force; as, to coerce a bad man by punishments or a prisoner with fetters. It has now gained a positive sense., viz., that of driving a person into the performance of some act which is required of him by another; as, to coerce a man to sign a contract; to coerce obedience. In this sense (which is now the prevailing one), coerce differs but little from compel, and yet there is a distinction between them. Coercion is usually acomplished by indirect means, as threats and intimidation, physical force being more rarely employed in coercing.
Shades of meaning
Fernald has no entry of its own for coerce; he lists it under compel.
Where he writes about it:
Coerce implies the actual or potential use of so much force as may be necessary to secure the surrender of the will; the American secessionists contended that the Federal government had no right to coerce a State. — from compel