From Longman Dictionary of Contemporary Englishit’s not every day (that)it’s not every day (that)OFTEN#used to say that something does not happen often and is therefore very special Let’s go out and celebrate. After all, it’s not every day you get a new job. → day
Examples from the Corpus
it’s not every day (that)• It's not every day that a helicopter sits down in your backyard.• It's not every day a young woman pulls a gun on a burglar.• After all, it's not every day you win an arena referendum and a game against the defending champion Lakers.• Well, it's not every day, is it? 