Definitions for taciturnˈtæs ɪˌtɜrn
Random House Webster's College Dictionary
inclined to silence; reserved in speech; uncommunicative.
dour, stern, and silent in expression and manner.
Origin of taciturn:
1765–75; < L taciturnus=tacit(us) silent (see tacit ) +-urnus adj. suffix of time
habitually reserved and uncommunicative
Silent; temperamentally untalkative; disinclined to speak.
The two sisters could hardly have been more different, one so boisterous and expressive, the other so taciturn and calm.
Origin: From taciturne or taciturnus, from tacitus.
habitually silent; not given to converse; not apt to talk or speak