A "High School Musical" Jump is a picture taken of someone while they have jumped and are in mid-air. It is inspired by the popular "High School Musical" movie posters of the cast members jumping in mid-air (hence the title).
Joe: Let's take a picture.
Alex: Let's make it of a "High School Musical" Jump!
(As they jump and are in mid-air, the camera takes the picture.)
Something someone says during a long, akward silence to get people's attention and to start up a conversation.
(Long, akward silence)
Joe: (pointing into space) Oh my god, it's Bruce Willis!
Everyone else: Where!? I don't see him!?
To give someone a hickey.
A man and a woman were kissing when the man gave the woman a hickey. That is a "Vampire Bite".
TNRC is an acronym for "Technically Not Related Couple". A TNRC is a couple who are not married yet they live together.
Guy #1: So you're a TNRC?
Guy #2: Yeah! I am!
A man poking a female's ass with five fingers and kissing the girl on the lips.
A cute girl walked by a guy and the guy saw her ass and thought it was cute, so he poked it (i.e. a "Maroon 5") with his five fingers and kissed her.