From: http://www.bbc.co.uk/worldservice/learningenglish/language/2013/03/130319_todays_phrase_to_pop_your_head_out.shtml
Crocus flowers pop their heads out through a layer of fresh snow. Photo: AP/ Matthias Hiekel
Today's Phrase
If someone says they are going to pop their head out, they mean they are going to take a brief look outside.
Examples:
I'm just going to pop my head out and check the weather to see if I need to take an umbrella with me today.
Could you just pop your head out of the window please and see what's caused the traffic to stop.
Could you just pop your head out of the window please and see what's caused the traffic to stop.
Take note
If your eyes pop out of your head, it describes the look of complete surprise on your face when you see someone or something that is very unusual or surprising.
Example:
When John asked Jane to marry him and gave her a diamond ring, her eyes popped out of her head: it was completely unexpected.
Interesting fact
The British Autumn crocus flower was once used as a herbal treatment for inflammation. This is because it contains a chemical (colchicine), which is known to have medicinal properties, including anti-cancer effects. Scientists are now trying to use the chemical to treat tumours.