A mature cheddar head is someone who is very mature but acts really stubborn and stuck-up with it, quite snobby. They are mature in a really boring way with no sense of humour and take everything seriously.
'Sophie told me making fart noises is immature.'
'Don't worry, she's a mature cheddar head with no sense of humour.'
'Don't worry, she's a mature cheddar head with no sense of humour.'
by mousey1306 March 7, 2012
Extra Mature Cheddar refers to 'old money' that has been in a family for a minimum of 6 years. If somebody's ancestors inherited the family fortune, they're classed as an extra mature cheddar family.
by C L G July 4, 2021
Mature cheddar is slang for "old money". If somebody inherited their fortune, they are classed as mature cheddar.
by C L G July 4, 2021