- (idiomatic, informal) Something very important or difficult, or of great concern.
- It's a big deal to him to get this promotion.
- It's no big deal if you don't finish.
- (in expressions such as 'make a big deal of' and similar) Something made into a supposedly big or important matter, despite actually being quite minor.
- Why do you always have to make such a big deal of tiny punctuation errors?
something very important
- (idiomatic, informal, ironic) Indicates that something is not important or impressive; so what.
- He can run a mile in six minutes? Big deal! Some people can do it in four.