This word includes all different types of neurotransmitters. A medschool student can not grasp their complexity and misteriousness.
Oh wao, so many neurotransmithrandirs! Very misterious and complex, just like Mithrandir himself...
O-H means Original Hipster. Like Jack Kerouac or Jim Morrison. People who have a rockstar-attitude, live on the road, seem to be intlectuals and are heavily intoxicated by alcohol or other kinds of drugs.
Babongo: See that guy? He's lit!
Doejoe: I know that rockstar! He's f****** O-H!