n. A day taken off work due to (possibly exaggerated or supposed) illness.
n. A person with unpleasant tastes, views or habits.
n. A mentally ill person.
Word Usage
"And when some smarmy clueless sicko is watching you do this while asking you why it takes so long to count some pills and put them in a bottle, I can imagine the veins popping out of the pharmacist’s head now."