(Emergency Room Doctor) A derogatory term used to describe someone who is up to date or knows what's going on in a situation, but loves to inform others of their perceptiveness. Usually used sarcastically.
Horatio: This John Doe obviously died of auto erotic asphyxiation*puts on sunglasses* What a wanker...
Bystander: Wow! That Horatio detective dude is a real ER-Doc. He definitely has his finger on the pulse.
Horatio: Arrest that bystander! He must have committed the murder! Only a wanker would make a pun that bad!
Nurse: Quick! This patient is flat-lining!
ER Doctor:*checking pulse of patient* Hurry up people! This patient is dying!