Musk has now expanded to mean going hard on anyone or anything. Much like "going HAM", musk is a state of mind. To musk is to fully rip into the situation and go 110%.
One can either go musk, musk on, or simply musk, depending on context.
Musk can also be interchanged with virtually any lyric in popular music to create a musk anthem.
"If you're going to pay $1500 to go on Spring break, you better be musking THE hardest"
"Last night I totally went musk on John. I can't remember the last time we had such crazy sex"
"Musk so hard muskafuckas wanna musk me"
Generally causes arousal for both genders, as it is a secondary sex characteristic.