An idiom, developed in the late 1800's, that nowadays is used in the literal sense: that the person saying this, is telling the person receiving that their mother, is in fact a homosexual , or merely as an insult, that makes no literal sense. But in its half century (or so) of use was in the actual sense of an idiom; in that it could be used in a slightly more nonlinear sense.My analysis of the idiom:I first like to look at the use of the work "you're" which is the contraction of the words "you are," which I can believe is a way to really emphasize how personal the use of the phrase can be. Then there's the word " mom ," the person who birthed you, the reason that you're currently on this world. Now many people are upset whenever you talk about their mother in a negative sense, and since this is right before the word " gay ," whose definition relates to being attracted to the same sex which is taboo in culture today, and was much more in previous centuries, many believe this to have a negative connotation while in conjunction with the word "mom." But I find it to have been used in a much lighter sense in previous centuries, not being used as an insult, but more a compliment generally meaning "your mother is quite lighthearted," since gay isn't just a way as classifying someone as being attracted to the same sex, but also as an adjective to describe a good