I watch quite a lot of YouTube and Twitch videos, and I came across ‘‘Senpai’’ so many times recently.
I suppose it’s a teenage culture thing (in USA, I guess) but why did the word get so much popularity?

So my question is:

Where does ‘‘Senpai’’ come from?
Which TV drama or animation does the word originate from?

I googled “senpai” and found the site as below.

I also found the anime video named “Senpai Club” on YouTube.

Your senpai at LingQ.

(I always saw it spelled sempai, but google tells me it’s spelled senpai). Senpai is just senpai: Senior or mentor; social superior. Just like it is in Japanese (more or less, of course. Linguistic drift and the telephone game and all that). And it comes from every anime ever. A lot of Japanese culture is transmitted to us Western nerds via anime and console games, and especially early on, we had to watch it all in badly-subbed Japanese, so we got a lot of it quite raw and untouched by a cultural transliteration brush. So some words, especially honorifics, made it into the anime-nerd vocabulary. -chan shows up a lot too.

Ahh yes. Back in my Kyokushin Karate days, we referred to the senior student as senpai. I got my black belt/shodan and I was referred to as senpai while we referred to the instructor as sensei, and the senior instructor (6th dan or higher) as shihan.

Senpai comes from “先輩,” which is pronounced se-n-pa-i.

Thank you everyone.

It looked to me that ‘‘SENPAI’’ came out from nowhere.
It’s strange to see such a specific foreign word can spread out quickly and get accepted universally.