Keenen is a unique and distinctive given name of Irish origin, meaning "ancient" or "old." It is derived from the Irish name Cianán, which is composed of the elements 'cían' meaning old, ancient, and 'án' denoting little one. This name has been used sparingly throughout history but has seen a slight increase in popularity in recent years. The variant spellings Keenan and Kienen are also occasionally encountered. In its native Ireland, Keenen is sometimes associated with the Irish surname O'Keenan, which originates from the same root as the given name.
"Keenen saw its peak popularity with 134 births in 1991, followed by a steady decline to just 6 births in 2022."