From Longman Dictionary of Contemporary Englishopen to doubtopen to doubtDON'T THINK SO/DOUBT ITsomething that is open to doubt has not been proved to be definitely true or real The authenticity of the relics is open to doubt. → doubt
Examples from the Corpus
open to doubt• But the political and military efficacy of the pacts was always open to doubt.• Faith is something which is merely believed, so it must always expect to be open to doubt.• Whether this kind of Labour Party is capable of winning a general election is open to doubt.• But whether that amounts to a positive incentive for companies to boost production and revive investment plans is open to doubt.• Whether it will help in breaking two-party politics is open to doubt.• Whether it will ever be finished is now open to doubt.• Of course, even if accurately transmitted the reliability of this poetry is still open to doubt.• Further, and more important, it was open to doubt whether the nobility was properly trained for war. 