Examples:

• Yes, but I don't attach any importance to that sort of old wives' tale.
• That's an old wives' tale, Bob.
• That's an old wives' tale.
• If leave the house with wet hair I can catch a cold. - That's an old wives' tale, Melinda.
• Eat the chicken soup because it will make you feel better. - Really, it's more than an old wives' tale.
• But for centuries, it was an old wives' tale.
• Well, the name comes from an old wives' tale.
• Apparently that's not just an old wives' tale.
• That one seems to be an old wives' tale.
• Fairly convinced this is an old wives' tale, but we shall see.