A word used by middle-aged men to describe someone who is cool. 'Coolcat's' will often listen to vile dad rock, i.e. Status Quo. The term 'coolcat' can also be used in a sarcastic manor, directed towards someone who believe they are cooler than they actually are.
'Hey, what's wrong? Is your dad not enough of a 'coolcat' to be hanging around at your school prom?'
'Oh your boy friend is a bit of a b
with that flowered shirt, isn't he?'