I think you're all labouring under a misconception that the word refers to " green sleeves" That is just a recent mis-hearing. The song actually was written about "greens leaves",and was a sort of exhortatory lullaby type song encouraging children to eat up their cabbage. Well, that'd what my reacher used to say: so forget about the prostitute harpists. Next week's topic: The foggy foggy dew.