Although use of the word "lemon" these days might make a person think of a defective car and a lawsuit handled by a California lemon law attorney, the term has actually been in use for quite a while and was used to describe other circumstances than what might be discussed in San Diego lemon law. For example, around the turn of the last century, the British would use the word to describe an article that was being offered as a good example of writing when it was in fact sub-standard.  The word lemon was also used to describe a hustle in a pool hall about a hundred years ago.