WordNet records no synonym and no antonym for bank run. 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.
the concerted action of depositors who try to withdraw their money from a bank because they think it will fail
Synonyms, antonyms and the broader and narrower relations for bank run come from Princeton University’s WordNet. Full sources and licences.