Meaning of the word "nothing so bold as a blind mare" in English

What does "nothing so bold as a blind mare" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

nothing so bold as a blind mare

US /ˈnʌθ.ɪŋ soʊ boʊld æz ə blaɪnd mer/
UK /ˈnʌθ.ɪŋ səʊ bəʊld æz ə blaɪnd meə/
"nothing so bold as a blind mare" picture

Idiom

used to describe someone who acts with extreme confidence or recklessness because they are unaware of the dangers or consequences

Example:
He invested all his savings into that risky startup; truly, nothing so bold as a blind mare.
She challenged the champion without any training, proving there is nothing so bold as a blind mare.