fidelity

Fidelity is a notion, that at its most abstract level implies a truthful connection to a source or sources. Its original meaning dealt with loyalty and attentiveness to one's duty to a lord or a king, in a broader sense than the related concept of fealty. Both derive from the Latin word fidelitas, meaning "faithfulness."

In modern human relationships, the term can refer to sexual monogamy. In western culture this often means adherence to marriage vows, or of promises of exclusivity or monogamy, and a lack of adultery. However, some people do not equate fidelity in personal relationships with sexual or emotional monogamy. (For example, see polyamory.)

Fidelity also denotes how accurate a copy is to its source. For example, a worn gramophone record will have a lower fidelity than one in good condition, and a recording made by a low budget record company in the early 20th century is likely to have significantly less audio fidelity than a good modern recording. In the 1950s, the terms "high fidelity" or "hi-fi" were popularized for equipment and recordings designed for more accurate sound reproduction, while "lo-fi" music aims for "authenticity" over perfect production. Similarly in electronics, fidelity refers to the correspondence of the output signal to the input signal, rather than sound.

In religion, the fidelity of God is said to refer to His devotion, faithfuless and commitment toward all creations, as exemplified in the Old Testament of the Bible.