The usage of 土日, 週末 and 休日

Question

I noticed this when I was listening to Momoiro Clover Z's 「行くぜっ！怪盗少女」, which had this line: 「土日｛どにち｝はよろしくね　週末ヒロインです」. I understand that 土日 means 土曜日 + 日曜日 = weekend, i.e. 週末. Thus, can 土日 and 週末 be used interchangeably, or are there different nuances in 土日 and 週末?

There is also the term 休日, which I understand as referring to "days off", i.e. weekends plus public holidays 祝日. However, can 休日 be used interchangeably with 週末/土日 as well? (Because I think I might have seen this usage in Japan, but I may be wrong.)

Answer 1

土日 and 週末 are very similar, but 週末 vaguely refers to weekend, while 土日 is explicitly Saturday and Sunday. Friday nights are usually considered as part of 週末, but not part of 土日. While 週末ヒロイン sounds like a nice coined phrase, 土日ヒロイン sounds a bit too strict and funny to me. Travel magazines often have articles titled ～で週末を楽しむ, but usually not ～で土日を楽しむ.

休日 refers to days off. You don't necessarily have to have days off on Saturdays and Sundays, so 休日 is different from 土日/週末.