What is it? Liking sports?...liking sex?....peeing standing up?.....having a penis?

What makes a man?
_________________________
"When I was a child
I caught a fleeting glimpse
Out of the corner of my eye
I turned to look but it was gone
I cannot put my finger on it now
The child is grown, the dream is gone
And I have become comfortably numb."
Pink Floyd