爷青回yé qīng huí

爷 means “grandpa” or “sir”, and online it is a swaggering way to say “I”. 青 stands for 青春, “youth”, and 回 for 回来了, “has come back”. Part of the joke is that young people call themselves “grandpa” while they talk about their youth.

The opposite is 爷青结, “my youth is over”, for when a show ends, a band splits or a favorite place closes.

爷青回 is still common, on Bilibili and everywhere else. It works for a reunion, a remake, an old snack back in shops or an old game back online.

Some people use it sarcastically, about a video that copies an old trend or a creator who posts very late.

It began as a 弹幕, a bullet comment that flies across a video on Bilibili. In 2020 Bilibili users sent it more than 5.4 million times, the most of any comment, and the site named it the comment of the year.

The videos with the most 爷青回 that year included the 1986 TV series Journey to the West, which the site put online that summer, and old anime theme songs. That December the Shanghai paper 语言文字周报 put it on its list of the ten internet phrases of 2020.