Restraint, n.
Etymology: [OF. restraincte, fr. restrainct, F. restreint, p. p. of restraindre, restrendre. See Restrain.]
1. The act or process of restraining, or of holding back or hindering from motion or action, in any manner; hindrance of the will, or of any action, physical or mental. No man was altogether above the restrains of law, and no man altogether below its protection. Macaulay.
2. The state of being restrained.
3. That which restrains, as a law, a prohibition, or the like; limitation; restriction. For one restraint, lords of the world besides. Milton.
Syn. -- Repression; hindrance; check; stop; curb;
Shades of meaning
Fernald has no entry of its own for restraint; he lists it under barrier.
He lists it without comment; the entries above explain its neighbors.