fidelity
fih-DEL-ih-tee
/fɪˈdɛlɪti/
Faithfulness to a person, cause, or belief, demonstrated by continuing loyalty and support; in medicine, the duty to keep promises and be loyal to the patient.
Fidelity includes both keeping explicit promises (like an appointment) and implicit ones (like the promise to act in the patient's best interest).
The story behind the word. From the Latin 'fidelitas.' It has always carried the sense of being 'true to one's word.' In the Middle Ages, it was the core of the knightly code.
Word relationships
- loyalty: Loyalty is a general feeling of support; fidelity is a more formal, often duty-bound faithfulness.
- infidelity: The action or state of being unfaithful.
Commonly confused with
- fealty: Fealty is specifically the loyalty of a vassal to a feudal lord.
Word family
- fides (noun): The Latin root for faith.
Collocations
- professional fidelity
- marital fidelity
- high fidelity
Example sentences
- "The nurse's fidelity to her patients meant she stayed past her shift to ensure the handover was handled correctly." Professional ethics.
- "Fidelity is the virtue of being faithful to one's commitments." A classic definition.
Memory hook
Fidelity is like 'Fido' the dog—always faithful and loyal. Keeping the promise.
When not to use
Don't use it for audio quality ('high fidelity') in an ethics essay unless you're making a very clever pun.
Fun facts
- The US Marine Corps motto, 'Semper Fidelis' (Always Faithful), uses the same root.
Related words
Explore more words
infidelity, devotion, fealty, disloyal, allegiance, steadfast
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