when you text a guy hi and he responds with Hi girl :)
Most Helpful Girl
hmm it could mean he's gay...my gay friends respond with hey girl sometimes and smiley faces
it could mean he forgot your name and have you as girl in his contacts
It could mean that it means nothing at all besides what it says it means which is a simple greeting and you should just respond with hey boy do you always respond with hey girl ? just to start a conversaton. (woo lack of punctuation in that one)
hopefully you continued texting him and then you could quickly confirm whether or not his responses are good or bad or if you are even interested.