Meaning: Its source is Cinneidigh, an Irish Gaelic name meaning "Helmet head."

Narrative: This surname might have originated as the nickname of a hard-headed warrior. However, its use as a personal name in modern times can probably be attributed to the Kennedys of Massachusetts, a family prominent in American politics for three generations.

The name is especially likely to be given in honor of President John F. Kennedy, murdered in 1963 while still in office, and his brother Bobby Kennedy, who was assassinated in 1968 while campaigning for the presidency.