Meaning of the word "know somebody/something inside out" in English

What does "know somebody/something inside out" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

know somebody/something inside out

US /noʊ ˈsʌm.bə.di ˈsʌm.θɪŋ ˌɪn.saɪd ˈaʊt/
UK /noʊ ˈsʌm.bə.di ˈsʌm.θɪŋ ˌɪn.saɪd ˈaʊt/
"know somebody/something inside out" picture

Idiom

1.

to know someone or something extremely well

Example:
She's worked here for twenty years, so she knows the company inside out.
He's a local, so he knows this area inside out.
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