WordNet records no synonym and no antonym for thermography. It is the only member of its synset, 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.
diagnostic technique using a thermograph to record the heat produced by different parts of the body; used to study blood flow and to detect tumors
Synonyms, antonyms and the broader and narrower relations for thermography come from Princeton University’s WordNet. Full sources and licences.