What do the leaves feel like? Are they thick and waxy, rough and leathery, smooth and thin, or something else? Does the sap have a scent? Also, does it ever produce fruit? If so, what does it look like?
Sorry for all the questions, but there are a lot of plants that look exactly like this, and it can be hard to identify them without a lot of information.
It looks sort of like a cherry laurel or a very large Clethra alnifolia, but it's hard to tell without more information.