What does 今日という日 mean?


I'm trying to translate a song lyric that says

> 今日という日は 過去 前例のない  
>  僕たちの誓い日和だよ

And I get a dictionary result at Jisho for 今日という日 as something like every day;
all day but that doesn't make any sense to me. I can't muddle thru it on my
own and I'm hoping someone here can explain was this phrase means. The best I
got is "today like every day" but my Japanese isn't very good.




今日という日 (literally "the day called today") is just an emphatic version of
"today", or "this very day". This expression is commonly used in formal
greetings and poems. (I tried jisho.org but got nothing related to "everyday".
How did you come up with "everyday"?)

