From Longman Dictionary of Contemporary Englishold wives’ taleold wives’ taleBELIEVEa belief based on old ideas that are now considered to be untrue → old
Examples from the Corpus
old wives’ tale• It's not true that if trees have a lot of fruit in the autumn it will be a cold winter - that's just an old wives' tale.• Some dismiss these as myth in the sense of old wives' tales.• That's only an old wives' tale.• Whatever doctors, old wives' tales, and the Roman Catholic Church may say, human ovulation is invisible and unpredictable.• And so the old wives' tale continues.• The old wives' tales that have answered the pleas of fathers for centuries are mostly ineffective.• I think it's an old wives' tale that make-up ruins the skin. 