形容詞 reticent:

1. temperamentally disinclined to talk
   同義詞：untalkative
2. cool and formal in manner
   同義詞：reserved, restrained, unemotional
3. reluctant to draw attention to yourself
   同義詞：self-effacing, retiring

1. He seems unduly reticent on the subject of his past.
   他似乎對他過去的事情諱莫如深。

ret.i.cent

adj.（形容詞）
Inclined to keep one`s thoughts, feelings, and personal affairs to oneself.See Synonyms at silent
沉默寡言的：傾向于保留某人的想法、感情及個(gè)人事務(wù)的參見 silent
Restrained or reserved in style.
有節(jié)制的：在風(fēng)格上受限的或保留的
Reluctant; unwilling.
不情愿的；勉強(qiáng)的

來源：
Latin reticôns reticent- [present participle of] reticôre [to keep silent]
拉丁語 reticôns reticent- [] reticôre的現(xiàn)在分詞 [保持沉默]
re- [re-]
re- [表示.再.]
tacôre [to be silent]
tacôre [沉默]

【引伸】
ret.icently
adv.（副詞）