An interglacial period (or alternatively interglacial) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial has persisted since the end of the Pleistocene, about 11,400 years ago.
Read more about Interglacial: Interglacials During The Pleistocene, Interglacial Optimum