Meaning of the word "(stark) raving mad" in English

What does "(stark) raving mad" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

(stark) raving mad

US /ˈstɑːrk ˈreɪvɪŋ mæd/
UK /ˈstɑːk ˈreɪvɪŋ mæd/
"(stark) raving mad" picture

Idiom

completely mad or insane

Example:
He must be stark raving mad to think he can climb that mountain in winter.
The old man was stark raving mad, muttering to himself in the street.