The cloaca is a common rear opening in land vertebrates.

To begin with, the rear opening was a single unit, hinged at the top.

The word 'monotreme' refers to their common rear opening, the cloaca.

It was designed that way so very large objects could be run into the rear opening.

The Shadow had led the way through to a rear opening between two buildings.

These mammals are called monotremes because they have a common rear opening known as the cloaca.

Two soldiers took up positions on either side of the rear opening.

The man raced out the rear opening in the island and raced toward the back door!

The two darted across the tent and out through the rear opening.

I poked my head out the rear opening and looked toward the front of the truck.