From Longman Dictionary of Contemporary Englisha grain of somethinga grain of somethingLITTLE/NOT MUCHa very small amount of something The story wouldn’t have fooled anyone with a grain of sense. There is a grain of truth in all folklore and legend. → grain
Examples from the Corpus
grain of truth• Although it contains a grain of truth, this theory rather radically misses the mark.• It was a gross exaggeration, but there was a grain of truth in it.• But there was a grain of truth in there.• True, most of these beliefs contain grains of truth, but their omnipotent power does not survive close scrutiny.• So Mr Murray's criticism does have an important grain of truth in it.• The Oracle's answers should have some grain of truth.• These two true incidents have in their implications a strange grain of truth. 