serum hepatitis has 1 distinct synonym spread across 1 of its 1 sense. 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. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
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.
an acute (sometimes fatal) form of viral hepatitis caused by a DNA virus that tends to persist in the blood serum and is transmitted by sexual contact or by transfusion or by ingestion of contaminated blood or other bodily fluids
Synonyms, antonyms and the broader and narrower relations for serum hepatitis come from Princeton University’s WordNet. Full sources and licences.