A copse is a thicket of bushes or a small stand of trees. A copse of trees can provide a good hiding place during a game of hide-and-seek.
If you go to your local garden shop and ask about how to take care of your copse, you may get some blank stares, as it's not a word you'll find much in everyday use. The word first appeared in the late-sixteenth century, as a shortened form of coppice, a word still used in British English, referring to an area with trees or shrubs that are periodically cut back to the ground so that they grow back thicker.
