Looking a little annoyed, she left it, and he went.

[sitifan]

'I have one or two people coming in tomorrow evening. Why not join us?’
I turned away so that I did not have to watch him search for an excuse.
‘I’m so sorry,’ he said, ‘tomorrow I am probably driving to Sospel; I’m not sure when I shall get back.’
Looking a little annoyed, she left it, and he went.
(Rebecca, by Daphne du Maurier, simplified and abridged by A. S. M. Ronaldson) http://lib.bbu.edu.az/files/book/1039.pdf

What does the clause "she left it" mean?

 

[emsr2d2]

The imperative "Drop it!" is commonly used (in the UK, at least) when you want someone to stop talking to you, or asking you questions, about a particular subject.

John: Are you dating Helen?
Sarah: That's not really any of your business.
John: Oh, come on. Are you?
Sarah: I don't want to talk about it.
John: Don't be silly. We're friends. You can tell me anything.
Sarah: That's not the point. I don't feel like discussing it.
John: This is ridiculous. Are you dating her or not?
Sarah: Just drop it!!!!!
John: OK, don't get your knickers in a twist. I was only asking.
Sarah: Well, don't.

 

[jutfrank]

We do say Just leave it also, in the same way as emsr2d2's Just drop it! in the dialogue above.

 

[emsr2d2]

Apologies for any confusion. I meant for my dialogue to exemplify the word used in post 1 and then I got distracted by Piscean's mention of "drop". I meant to use "Leave it/Just leave it" in my dialogue. As jutfrank pointed out though, they are both used.

"Leave it" crops up a lot in EastEnders, the UK soap opera set in the East End of London. It's usually said when someone in the pub is about to punch someone in the face, and someone else tries to defuse the situation with "Leave it! He's not worth it!" or similar.