it's not everyday

Phrase

followed by a complement

(followed by a complement) it is not very common (that)

Japanese Meaning

日常的なことではない / 普段はあまり見られない / めったに起こらない / 珍しい・特別な

I realized it's not everyday that you get to watch the aurora from your backyard.

裏庭からオーロラを見ることができる機会は、毎日あるわけではないと気づきました。

Sense（1）

(followed by a complement) it is not very common (that)

It's not everyday you see a black swan.