"Loyalty" is a noun that refers to a quality of faithfulness, commitment and support. The trait of loyalty is highly valued in organizations and in personal relationships.
The quality of loyalty characterizes fans of all sorts as well as ideal romantic mates and members of congregations, political parties and corporations. Dogs boast a reputation for unconditional loyalty to their owners. A "loyalty program" is a popular form of customer incentive, where users of a service earn rewards for doing business with a company. Steadfastness, dedication and allegiance are synonyms for loyalty. Betrayal, treachery and disloyalty are some of the word's antonyms.