diffident

形容词 diffident:

1. showing modest reserve
2. lacking self-confidence
   同义词：shy, timid, unsure

1. He is diffident about expressing his opinions.
   他对于表达自己的意见感到胆怯。
2. The quality or state of being diffident; timidity or shyness.
   缺乏自信; 胆怯缺乏自信的性质或状态; 胆小的或羞怯的

dif.fi.dent

adj.（形容词）
Lacking or marked by a lack of self-confidence; shy and timid.See Synonyms at shy
缺乏自信的；羞怯的和胆小的参见 shy
Reserved in manner.
踌躇的：方式上采取保留的态度

来源：
Middle English
中古英语
from Latin diffodôns diffodent- [present participle of] diffodere [to mistrust]
源自 拉丁语 diffodôns diffodent- [] diffodere的现在分词 [不信任]
dis- [dis-]
dis- [前缀，表相反的意思]
fodere [to trust] * see bheidh-
fodere [相信] *参见 bheidh-

【引伸】
dif.fidently
adv.（副词）