WordNet records no synonym and no antonym for pathology. It is the only member of each of its synsets, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
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.
the branch of medical science that studies the causes and nature and effects of diseases
any deviation from a healthy or normal condition
Synonyms, antonyms and the broader and narrower relations for pathology come from Princeton University’s WordNet. Full sources and licences.