Hey there! As I said in the title, there is a difference between 休日 and 休み pertaineing to the meaning of “vacation”. WK doesn’t accept “vacation” as 休日, while Jisho considers it as an outside source meaning. It says that the Noun means “Holiday, day off” and then also says that Wikipedia says that it means “vacation”.
I’m not sure why Jisho does choose to translate it as such. 休日 is specifically a day off that you didn’t request yourself, and as the word already suggests refers to a single day (unless it’s plural) and not to an arbitrary period off work like 休み does. Could be a holiday, could be the company is closed that day, could be the boss told you not to come into work, but it’s not a day or a few days off you requested (my dictionary specifically says 休日」は自分の申し出による休みではないので「─を取る」とはいわない。).
“Vacation” seems a bit of a stretch under those considerations - at the very least I wouldn’t ever refer to something like Whit Monday as such. Maybe in the sense that something like a school vacation could qualify as multiple 休日?
Are you asking why Jisho lists vacation for 休日? That’s merely because the 休日 and Vacation Wikipedia articles are linked to each other (or were at some point) and Jisho automatically adds the corresponding English Wikipedia article title to its entries.
Jisho can’t control what Wikipedia links to what, and reviewing them all seems like a big ask for the solo creator.
Thanks for your answers guys! What I was confused about was the nuances of the word 休日. Now I get that it’s supposed to be a national holiday or just being told not to go to work for whatever reason, so something that happens outside your control. This definition doesn’t include “vacation”. Meanwhile, 休み does because it’s something you choose to do.