Two Left Feet
Two left feet is an anatomical condition in which a person is born with a left foot on his or her left leg and a left foot on his or her right leg. Though it may not limit walking or any other activities of daily living, it completely inhabits a person's ability to dance, hence the phrase two left feet. Not many people know that it's a real condition, so take care in making that comment. Interestingly, people with two right feet dance awfully well.