Meaning of the word "from the horses mouth" in English

What does "from the horses mouth" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

from the horses mouth

US /frʌm ðə hɔrsɪz maʊθ/
UK /frɒm ðə hɔːsɪz maʊθ/

Idiom

from an original, authoritative, or reliable source

Example:
I heard it straight from the horse's mouth that the company is merging.
You can trust this information; it came from the horse's mouth.