"Loyalty" is a noun referring to a state of faithful commitment a person makes to another person, group, place or thing. From a leadership perspective, a loyal follower is someone who follows a leader's directive with complete faith and trust. A loyal friend similarly commits to supporting someone.
Faithfulness, allegiance and fidelity are common synonyms for loyalty. In business, customer loyalty refers to situations in which a customer forms an emotional attachment to a company. This attachment typically evolves over the course of a series of strong, positive experiences related to service, product quality or other critical factors. The term "loyalty" originated from 14th-century Middle English and Middle French.