The farmer granted the power company an easement to install power lines across his land.

easement 是法律术语，来自动词 ease（减轻、使便利）加名词后缀 -ment，指"为他人提供便利而对自己土地权利的限制"。在不动产法中特指"地役权"，即允许他人在自己土地上通行或架设设施的权利。