brave: 人や行為が勇敢であることをいうのに最もよく使われる語

courageous: 確固たる勇敢さを示す〘ややかたい〙 語

bold: action, step, moveなどと結びつき, 行動の思いきりの良さを示す

fearless: 人の大胆さをほめる語

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1. (of a person, action, or idea) showing an ability to take risks; confident and courageous:

〈人･行為が〉恐れを知らぬ, 大胆な, 果敢な

e.g. a bold attempt to solve the crisis

e.g. he was the only one bold enough to air his dislike.

dated (of a person or manner) so confident as to suggest a lack of shame or modesty:

〈人･行為が〉厚かましい, ずうずうしい

e.g. she tossed him a bold look.

2. (of a color or design) having a strong or vivid appearance:

〈色･形などが〉際立った, (派手で)目立つ; 〈線などが〉くっきりした

e.g. a coat with bold polka dots.

of a kind of typeface having dark, heavy strokes, used especially for emphasis.

〘印〙 太字体の, ボールド体の(bold-faced)

a bold typeface or letter:

〘印〙 ＝ boldface

e.g. difficult words and phrases are highlighted in bold.

formal dare to do something (often used when politely asking a question or making a suggestion): what would he be calling for, if I might make so bold as to ask?

confident to the point of impudence: she marched into the library as bold as brass.

a daring action or initiative:

e.g. the budget was full of bold strokes.

Old English bald, of Germanic origin; related to Dutch boud and to German bald ‘soon’.