Caramel liqueur is a type of liqueur flavored, either artificially or naturally, with caramel. Caramel liqueurs typically have a buttery-creamy richness to them, but better quality versions capture the burnt sugar edge that balances the overt sweetness of the liqueur.
[ingredient=baileys Baileys] and Godiva make widely available versions of caramel liqueurs. One better producer which is more difficult to find is [ingredient=briottet Briottet].