The `OMG` hitmaker - who has two sons, Usher V, two, and 23-month-old Naviyd, with ex-wife Tameka Foster - thinks a girl`s back can be the most attractive part of her body, but insists he is attracted to more than just looks.
He said: "The small of a woman`s back is sexy. There is a tenderness a woman has that could make a man fall to his knees and a strength that will tell him to be the greatest of all. For a woman to be able to dominate and also be feminine and soft, that`s a talent.
"And it`s not all about appearance. A woman who has a brain, who is street-smart and book-smart - that woman is very, very sexy to me."
The 32-year-old star also spoke of the importance of communication in making a relationship work.
Usher - who released his sixth studio album `Raymond v. Raymond` this year - said: "Women see things that men don-t. I guess it`s more important for a man to hear a woman, not just listen.
"The perfect relationship is one where both parties try to understand what their mate is not just saying, but feeling too."