Popularity today: #8
Nicknames: Bill, Billy, Will, Willie
Variants: Willem, Wilhelm, Liam, Guillermo, Guillaume
Sisters: Mary, Margaret, Cecelia, Anna, Catherine
Brothers: James, Joseph, Edward, Robert, Charles
Dominant a century ago, William has remained a robust, adaptable classic. It's distinguished but not a bit stuffy. The nickname Bill was among the essential 20th century names, while the smoother Will looks like a 21st century winner. Among such trendsetting groups as Ivy Leaguers and uptown New Yorkers, the name is soaring.