Presentaion:/ˌprɛz ənˈteɪ ʃən, ˌpri zɛn-/ Set number of agonizing minutes of exclusive divided attention (divided among you & your lousy slides, facebook, youtube, email, myspace, text messages, chats + other cool websites and iphone apps) intended for explaining to a group of unwilling students what took you 3 weeks to partially understand and one night to put on powerpoint.

Something you give without any type of obligation.

to give a presentation or performance. Often used as an enhancement to the word "present"

A pre-emptive resentment; getting pissed before anything actually happens.

when a gay shows his ass to sum1

unreciprocated oral sex (not reciprocated with sex either).

Cocaine (UK slang)