Big head tax

The extra tax charged to arrogant snooty big heads up their own arse that buy stupidly expensive things (e.g. cars)

Oh look at that big head Dave with his brand new Audi R8..
Reply: Wonder how much big head tax he gets charged for owning that..

Fronday to Miday

When someone is going away from Monday to Friday but you've had a brain fart and the letters switch round

Hey I didn't know Brenda was going away from Fronday to Miday, what's she doing with the dogs?

Grownupness

When you give an older kid between 8 and 15 some responsibility to look after their own money or to walk to the shop alone, this gives them a feeling of grownupness

I'm going to give John his own wallet with his own cash so he's got that grownupness feeling,

Did you like that grownupness when I let you go to the shop on your own?