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every day

Every day - here every is a determiner and day is a noun, so it is written as two distinct words.

When you say every day you mean each day without exception.

For example: You have been late for school every day this week.

Everyday is an adjective, and is written as one word.

When you say everyday you mean ordinary, unremarkable.

For example: My culture pages offer an insight into the everyday life of Britain.


!Note - if you want to check yourself see if you could write "every morning" or "every evening" without loss of meaning. Then you'll know it should be "every day".

I am reliably informed that in the US people happily use everyday for every situation.