Tierney is an uncommon yet distinctive given name, predominantly used for females. It originated from Irish Gaelic as a surname, derived from Ó Tigherna, which means 'descendant of Tiernan'. Tiernan itself comes from the Old Irish personal name Tighearnán, composed of the elements tighe ('king') and rían ('little king'). The name gained popularity in the United States during the mid-20th century.
"Tierney saw its peak popularity with 8 babies named Tierney born in the year 2006. Prior to that, it maintained steady popularity from 1976 to 1996, with an average of 5 births each year during this period."