is your pond frozen?

An ambiguous phrase referring to parts unknown. In Canada and other Temperate regions that suffer a large climatic range, frozen bodies of water may not be safe for a majority of the winter months. Is your pond frozen?, has of course been turned around for more devious uses.

It is often used as a "come on" term by men to find out if the object of their desire seeks to lay with them.

John: Hey Jill, is your pond frozen?
Jill: Oh John, you are such a pervert.