- 1
If you are diffident, you are shy in a quiet, self-doubting way. You do not push yourself forward. You would rather not be noticed, and you do not like people talking about you. A diffident smile is small. A diffident speaker may look down and keep their voice low, even when they have something good to say. It is a fairly formal, slightly adjective — teachers and novels use it more than teenagers on the bus. It is kinder than calling someone a coward, and it is about self-trust, not about fear of a tiger. The opposite mood in everyday English is confident. Though actually, this word started as “not trusting,” from Latin, and it is a of defiant: the two words split from the same old family and then went different ways. Defiant now means boldly pushing back. Diffident is almost the other posture. Do not swap them.
羞怯的、靦腆的、不敢出風頭的（書面語。不要看成 defiant「反抗的」——兩個字遠源有關，現在意思相反。）
組成From Latin diffīdentem, present participle of diffīdere “to mistrust” (dis- + fīdere “to trust”). Doublet of defiant: same old family, different path, different meaning now.
同家族的字
- diffidencethe noun for this shy, self-doubting feeling
- confidentthe everyday opposite: sure of yourself
- confidenceshares the Latin “trust” root, with a different prefix
- defiantetymological doublet; now means boldly refusing to give in, not shy
原始詞典資料2 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
diffidentadj/ˈdɪfɪdənt/
- 1
archaicLacking confidence in others; distrustful.
- 2
Lacking self-confidence; timid; modest
- Having therefore—but hold, as we are diffident of our own abilities, let us here invite a superior power to our assistance.
- Emma is spoiled by being the cleverest of her family. At ten years old, she had the misfortune of being able to answer questions which puzzled her sister at seventeen. She was always quick and assured: Isabella slow and diffident.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。