who's someone when they're at home
who's (someone) when (he's/she's/they're) at home
1. colloquial Who is that person? Primarily heard in UK. Robert De Niro? Who's he when he's at home? I've never heard of that actress before, who's she when she's at home?
2. How does someone act in the privacy of their own home? The phrase suggests that someone behaves differently or more authentically when at home. Do you ever wonder what big stars are like when they're not on stage or the red carpet? Like, who is Lady Gaga when she's at home, huh? I bet she doesn't wear a meat dress around the house!
See also: home
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
who's—when—'s at homea humorously emphatic way of asking about someone's identity. British
1991 Joseph O'Connor Mothers Were All the Same The old lady said to tell that to Yuri Gagarin , but the hostess just giggled and said, ‘Who's he when he's at home?’
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