WordNet records no synonym and no antonym for scanning. 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 process of translating photographs into a digital form that can be recognized by a computer
the act of systematically moving a finely focused beam of light or electrons over a surface in order to produce an image of it for analysis or transmission
Synonyms, antonyms and the broader and narrower relations for scanning come from Princeton University’s WordNet. Full sources and licences.