What does disloyalty mean?
Disloyalty is the noun describing a failure of faithfulness — a betrayal of the allegiance, trust, or support one owes to a person, group, cause, or nation. It covers everything from an employee who undermines her employer to a friend who breaks confidences to a citizen who aids an enemy state. The word carries strong negative weight: to call something an act of disloyalty is to condemn it as a breach of an obligation that ought to have been honored. In law, disloyalty can shade into treason or sedition, where the betrayal concerns the state itself. The term derives from "dis-" plus "loyal," tracing back through Old French "loial" to Latin "legalis," meaning lawful. Its everyday usefulness lies in naming not just wrongdoing but a specific kind of wrongdoing — one that violates relationship and duty rather than merely breaking a rule — which makes it central to discussions of ethics, politics, friendship, and organizational life alike.
The quality or action of being unfaithful or failing in allegiance to a person, group, cause, or country; betrayal of trust or loyalty.
"The general's disloyalty led directly to his arrest and court-martial."
Usually uncountable when referring to the abstract quality; takes the plural "disloyalties" for multiple concrete instances.
In legal contexts, conduct amounting to a breach of allegiance to one's sovereign or state, as in treason or sedition.
"Under the statute, publishing the documents constituted disloyalty against the crown."
Rarely used; "disloyalty" is normally uncountable. The plural appears only when enumerating distinct acts or instances of disloyalty.
"The report catalogued his many disloyalties over the years, each one documented."
Disloyalty was once a hanging offense — and in some countries it still carries the death penalty.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of disloyalty
Disloyalty comes from the adjective "disloyal," formed by adding the negative prefix "dis-" (from Latin) to "loyal." "Loyal" entered English from Old French "loial" or "leial," itself derived from Latin "legalis," meaning "of or pertaining to the law." Thus the root idea of loyalty was originally about being lawful and true to one's obligations. The word "disloyalty" has been used in English since at least the early modern period to describe breaches of both personal faith and political allegiance, with cognates such as "loyal," "allegiance," "leal," and "legal" all descending from the same Latin root.
Related word forms
How disloyalty is actually used
A formal-to-neutral word with strongly negative connotation, common in political, workplace, and moral discourse. It is an uncountable noun when describing the abstract quality ("acts of disloyalty") but can take the plural "disloyalties" when referring to multiple specific instances.
Easily confused with disloyalty
Infidelity typically refers specifically to unfaithfulness in marriage or a romantic relationship, whereas disloyalty is a broader term covering any failure of allegiance to a person, group, or cause.
Treason is the legal crime of betraying one's state, while disloyalty is a general moral failing that need not involve any crime.