Loyalty, n.
Etymology: [Cf. F. loyaute. See Loyal, and cf. Legality.]
The state or quality of being loyal; fidelity to a superior, or to duty, love, etc. He had such loyalty to the king as the law required. Clarendon. Not withstanding all the subtle bait With which those Amazons his love still craved, To his one love his loyalty he saved. Spenser.
Note: "Loyalty . . . expresses, properly, that fidelity which one owes according to law, and does not necessarily include that attachment to the royal person, which, happily, we in England have been able further to throw into the word." Trench.
Syn. -- Allegiance; fealty. See Allegiance.
Shades of meaning
Fernald has no entry of its own for loyalty; he lists it under allegiance.
Where he writes about it:
A patriotic American feels an enthusiastic loyalty to the republic; he takes, on occasion, an oath of allegiance to the government, but his loyalty will lead him to do more than mere allegiance could demand; he pays homage to God alone, as the only king and lord, or to those principles of right that are spiritually supreme; he acknowledges the duty of obedience to all rightful authority; he resents the idea of subjection. — from allegiance