The armpit of something American informal
The worst and dirtiest place.
Hinesville is known as the armpit of the world.
Do you know where is the armpit of our country?
People tell it is the armpit of the Europe, but I don't think so.
Despite being famous for industry growth, the city is the armpit of the country.
Go somewhere for a brief visit or purpose
1. If you hide away, you go somewhere so that no one can find you.
2. If you hide someone or something away, you put them in a place where people cannot find them.
To refer to an unfamiliar or faraway place.
Used to indicate a place full of valuable objects.
To leave a location to pursue something better
The idiom may come from the fact that the armpit is smelly, it can make a stink and offer bacteria.
To be very wet
Because of forgetting bringing an umbrella, I look like a drowned rat when it rains.