Does a male have to have abs to be y?

I am a 21 year old male, and I was just curious ladies do you have to have sharp defined abs to have a y body? Name some of your top male celebrities that you think is hot but dont have defined abs, but still has a nice slim body not muscular but slim? One that does not look like he works out constantly but looks healthy, if that makes any sense. Your thoughts would be greatly appreciated, thanks Dennis.