Posted in Government & Military, Internet Slang, Schools & Education YAG stands for Yttrium Aluminum Garnet YAG stands for You Are Great YAG stands for Youth and Government (Young Men’s Christian Association) YAG stands for Youth Advisory Group (various locations) YAG stands for Miscellaneous Auxiliary (Self-Propelled) YAG stands for You Are Gay YAG stands for District Auxiliary, Miscellaneous (US Navy) YAG stands for Young Alumni Group (various universities)