The act of being calm, silent, and serious. Those who choose to be stoic feel every emotion, yet show none. Never try to manipulate a stoic, because they always know what is going on. Some of the smartest people in the world are stoic. They keep their thoughts and feelings to themselves.
If silence is power, then stoicism is invincibility.
Teacher: You there!
Stoic Student: Yes?
Teacher: You failed your last test!
Stoic Student:......well then, I had better redeem myself soon.