According to Phoronix as well as a recent trademark registration by the Khronos group, Vulkan (volcano in german) is the new name of the upcoming new major version of OpenGL / glNext.
Vulkan trademark description:
Computer software, namely application programming interfaces for the purpose of creating, rendering, and displaying 2D and 3D computer graphics; computer software, namely application programming interfaces for the purpose of accessing parallel computing resources; downloadable specifications for the aforementioned goods.
More information will be revealed tomorrow at the GDC 2015.
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