Shtuph
When you are about to say shit but an uptight parent or teacher walks by and you change the ending of shit to tuph resulting in "Shtuph".
Friend 1: Man, we have so much homework.
Friend 2: Yeah, I hate this shhhh- *Teacher walks by* -shtuph.
Friend 2: Yeah, I hate this shhhh- *Teacher walks by* -shtuph.