Are you interested in making a second attempt at your motion? It's not allowed at the same meeting (unless your group's or organization's rules specifically allow it), but it is permissible at the next (and the next…not that we're suggesting that you make a pest of yourself). When a motion is presented again in its same form, it's called a renewal of motion.
If you feel you've learned something from the debate before it was voted down, and you've substantially reworded it, you should indicate this at the meeting so that it won't be mistaken for a renewal of motion. (Graciousness on your part can go a long way toward showing what kind of individual you are and, not so incidentally, can lead to the success of your motion as well!)
Main motions can't be renewed if they've been referred to a committee for study. This would essentially be taking away the ability of the committee to do its work. If you haven't been appointed to the committee, ask if you can appear before it to present your views for consideration.