fidelity has 1 distinct synonym spread across 1 of its 2 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is infidelity.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
accuracy with which an electronic system reproduces the sound or image of its input signal
Synonyms, antonyms and the broader and narrower relations for fidelity come from Princeton University’s WordNet. Full sources and licences.