poise, restraint, aplomb, self-government, discipline, self-discipline, reserve, reticence, self-restraint, discretion, balance, stability, sobriety, abstemiousness, dignity, repression, constraint, self-constraint, self-regulation.
Antonyms nervousness*, timidity, talkativeness.
"self-control." YourDictionary, n.d. Web. 24 May 2018. <http://thesaurus.yourdictionary.com/self-control>.
self-control. (n.d.). Retrieved May 24th, 2018, from http://thesaurus.yourdictionary.com/self-control
The keeping of one's thoughts and emotions to oneself: