From Longman Dictionary of Contemporary Englishlong shotlong shotsomeone or something with very little chance of success Chelsea are a 20–1 long shot to win the championship. → long
Examples from the Corpus
long shot• City officials and securities experts think the activists are betting on a long shot.• He had not told Rory everything, not by a long shot.• With all the interest the article had generated, Fanshawe no longer seemed like such a long shot.• This is a long shot, but I still want to try it.• It's a long shot, but well worth trying.• The 45-year-old candidate remains the longest of long shots for the Republican nomination.• Its brief revival was sparked by Dziekanowski who fed Tarasiewicz and for once a long shot had Shilton in trouble.• She had looked everywhere else and, although it seemed a long shot, she might as well look in there. 