Slang of the Day #12! ttyl/ttyt — texting slang for “talk to you later/tomorrow” ~~ -“I’m gonna go to bed now, ttyt!” bday/b-day — “birthday” (usually only used in writing) ~~ -“It’s Kent’s bday tomorrow!” bff — “best friends forever” (used in both writing and speech) ~~ -“I watched that movie with my bff last week.”