|Wesley comes from the combination of the directional word west, and the word lea, which means "meadow," "field," or "clearing." So Wesley can mean the clearing to the west, or the western field, etc. Wesley is a surname which signified someone who lived in such a place, or who was from one of the places in England which were given the name Westley. |
Many surnames have been transferred to use as given names, and the use often began as a means of naming a child for his mother's family, with her maiden name used as her son's given name. Wesley is one of these, but also received a boost in use from the founder of the Methodist Church, John Wesley, with many Methodists choosing name their sons Wesley in his honor.
Interestingly, Wesley has been a top 200 name in the U.S. for well over 100 years, with very little real variation--it has never been used enough to become over-used and too common, yet has never been rare. This may be partly due to the Methodist factor, but is probably also due to the fact that Wesley is a reasonably masculine and distinguished sounding name, common enough to not be "outlandish," yet it doesn't really invite nicknames or familiar forms that would bring it into more common use. Consequently, it's often used as a middle name.
Famous Wesleys include Wesley Snipes, and the character Wesley from television's Star Trek: The Next Generation. (Before someone yells at me for forgetting him, the character played by Cary Elwes in the movie The Princess Bride was named Westley, which is a simple spelling variation that makes sense for the setting of the book and movie.)