[French from Spanish albada, from alba (= French aube) dawn]
A piece of music or a poem written to be heard at or appropriate to dawn.
Would-be suitors beware - pulling out the aubade is a risky strategy. A little pre-wooing research might be in order, just to check that she is actually a morning person. And if it does all go Pete Tong, don't even think about returning at midnight to recite your hastily composed nocturne. Or maybe you should. I don't know. Just go for it. You've probably blown it anyway.