D defs.my
Entry 1 sense Webster, 1913

Taciturn

/tăs'-ĭt-ẽrnˌ/ · Tac·i·turn · IPA /ˈtæsɪtɝn/
01 a. Habitually silent; not given to converse; not apt to talk or speak.
  1. 1.
    Habitually silent; not given to converse; not apt to talk or speak.
Syn. Silent; reserved.
Taciturn, Silent. Silent has reference to the act; taciturn, to the habit. A man may be silent from circumstances; he is taciturn from disposition. The loquacious man is at times silent; one who is taciturn may now and then make an effort at conversation.