Czy szukales cos na Wikipedia? Ja znalazlam to:
....A lemon is a defective car that, when purchased new or used, is found by he purchaser to have numerous or severe defects not readily apparent before the purchase. Any vehicle with these issues can be termed a 'lemon,' and, by extension, any product which has major flaws that render it unfit for its purpose can be described as a 'lemon.'