See at a glance

[couch potatoe]

I've been triying to find the meaning of see at a glance but I didn't find it. Could you tell me what does it means?

Thank you.

 

[Raymott]

I've been triying to find the meaning of see at a glance but I didn't find it. Could you tell me what does it means?

Thank you.

The meaning is literal.
"I could see at a glance that she was sick."
That is, I didn't have to look at her for very long to realise that she was sick. I only had to glance (take a quick look) at her.