Korean ↔ English slang, explained by the people who actually use it.

Short for "knife-sharp clock-out" — leaving work exactly on time, the minute your hours end.

It is an abbreviation of "suddenly pops out."

A cute word for a dog — 멍멍이 ("woof-woof") rewritten as look-alike letters 댕댕이.

Short for "not reading and ignoring" — leaving a message unopened and unanswered, as opposed to 읽씹 (reading it and not replying).

Mountain + gym — using outdoor exercise equipment on hiking trails as your gym; it caught on when gyms closed during COVID.

Originally from a polite gamer sign-off ("enjoy the game"), it got shortened over time and repurposed to mean "forget it" or "get lost" — often used to shut down an absurd item-trade offer or dismiss someone outright.