Define "cool" - by: koochkooch

I'm having trouble understanding exactly what 'cool' means. I have a vague idea. Here are some of my own thoughts:
“an awareness of one’s own self confidence”
Having internal peace. Having ‘social control’ and ‘transcendental balance’
Composure and absence of excitement in a person in times of stress
Not relying on others for approval/support/consent for your own validation, yet respecting and abiding by specific social rules.
Having other ‘cool’ friends is cool
Backward caps and tattoos are cool
Deep, smooth, controlled voice is cool

Any thoughts? I want to get a scientific, concrete definition