Long before the name was presidential, Kennedy began as the Gaelic surname Cinnéidigh. It means "helmeted chief," and dates back to 10th-century Ireland. With time, Cinnéidigh was anglicized (given English spelling) as Kennedy.
The first person to bear this name may have been Cennétig mac Lorcáin, a king of Ireland who died in 951. When you look more closely at the origin of the name, it can be broken down into ceann, meaning head, and éide, meaning armor. Thus the meaning helmeted chief, or leader.
Kennedy's rise as a popular girls' name in the U.S. is certainly linked to a prominent family of Irish-American leaders. Former president John F. Kennedy, his brothers Robert F. Kennedy and Ted Kennedy, wife Jacqueline Kennedy Onassis, and son John Fitzgerald Kennedy Jr. were all famous for their wealth, style, and success – as well as the tragedy that marks their family tree.
Kennedy became a popular first name for boys in the 1960s, after President Kennedy was elected. It wasn't until 1994 that it took off for girls, landing on the Social Security Administration (SSA) list of top 1,000 girls' names at spot 524. Kennedy peaked for girls in 2014, when it was number 54 on the SSA list.
Among BabyCenter parents, Kennedy is also a popular name for girls. It's been in the top 100 names for several years. (BabyCenter's ranking is based on data from hundreds of thousands of parents who share their baby's name with us.)
The name Kennedy is pronounced "ken-nuh-dee," and less commonly, "keh-nih-dee." While it's traditionally spelled Kennedy, there are feminine variations spelled Kennedi, Kenedi, and Kennedie. And though it doesn't have a ton of nickname possibilities, Kenny, Nedi, or Kens all work.
Though it's an ancient name, Kennedy hits on several modern trends, such as gender-neutral names and last names used as first names. It appeals to parents with Irish heritage, as well as those seeking a strong name for their baby girl. Expect it to continue its streak as a popular name in the years to come.