old [adjective]

1. "Oude kaas": old cheese.
"Oude kaas" has a much sharper flavour than the standard "jonge kaas" (young cheese). Also its structure is crumblier. Types of cheese that are somewhere in-between are "jong belegen", "belegen" and "extra belegen".

2. "Oudejaarsavond": new year’s eve.
Literally this word translates to "old years eve", I guess it is just a different way of looking at it!

3. "Hoe oud ben jij?"
("How old are you?)

4. <saying> "Een oude bok lust nog wel een groen blaadje."
("An old goat still has taste for a green leave.")
This saying is used to describe the interest shown by old men in young women.

Dutch slang:
It is common in informal speech to replace the ‘d’ in ‘oude’ by a ‘w’: ‘ouwe’. Compare "ouwe snoeperd" in DWOTD 29. Snoep.
However, replacing ‘d’ by ‘w’ is only done with adjectives that have ‘oud’ at their core.

Another example is ‘koud’, which means ‘cold’. A person showing no emotions is sometimes called a ‘kouwe kikker’ ("a cold frog").