noun
principal object of worship; main image
Buddhist term for the central statue, painting, or object venerated in a temple or altar.
このお寺の本尊は阿弥陀如来です。
The principal image of this temple is Amida Nyorai.
Figurative extension: a person or thing that is worshipped or adored like a religious icon.
彼女は若者たちの本尊のような存在だ。
She is like an idol to young people.
noun
the man himself; the person at the heart of the matter
Jocular use, often with the honorific prefix ご (ご本尊), referring to the key person in a situation.
噂のご本尊がついに現れた。
The man himself, the one everyone was talking about, finally showed up.