The Blarney Stone (Irish: Cloch na Blarnan) is a block of Carboniferous limestone built into the battlements of Blarney Castle, Blarney, about 8 kilometres (5 miles) from Cork, Ireland. According to legend, kissing the stone endows the kisser with the gift of the gab (great eloquence or skill at flattery). The stone was set into a tower of the castle in 1446. The castle is a popular tourist site in Ireland, attracting visitors from all over the world to kiss the stone and tour the castle and its gardens.

The word blarney has come to mean "clever, flattering, or coaxing talk". Irish politician John O'Connor Power defined it this way: "Blarney is something more than mere flattery. It is flattery sweetened by humour and flavoured by wit. Those who mix with Irish folk have many examples of it in their everyday experience." Letitia Elizabeth Landon described its contemporary meaning in an article entitled 'Blarney Castle' in 1832.