I learned a new word today and I just had to share it! The word is ‘taciturn’ and according to Dictionary.com is an adjective that means, “inclined to silence; reserved in speech; reluctant to join in conversation.”
According to Thesarus.com the four closest synonyms are: aloof, dour, laconic, and reticent. There are 22 additional synonyms called out and my two favorites would be “reserved” and “unexpressive.”
For you serious etymologists out there here is the skinny on its origins: Taciturn ultimately derives from Latin taciturnus “keeping silent, saying nothing, silent by habit or disposition,” a derivative of tacitus, past participle of tacēre “to say nothing, be silent.” Tacēre and its derivatives come from an uncommon Proto-Indo-European root tak-, takē- “to be silent.” Tak- regularly becomes thah- in Germanic, yielding Gothic thahan “to keep silent, hold one’s peace,” and Old Icelandic thagna “become silent.” Tak- in Celtic yields Welsh tagu and Breton taga “strangling, choking” (one way of obtaining silence). Taciturn entered English in the 18th century.