Willis is an English surname meaning "son of Will", the short form of William, which goes back to the Germanic Willahelm and means "resolute protector". It was a common first name in the 19th-century South, and the catchphrase "What you talkin' bout, Willis?" from the sitcom Diff'rent Strokes made it a household word. Willis ranked number 1246 in 2000, its best recent position, and stands at number 2567 in 2025.