Gran is short for granulocyte. The White Blood Count (WBC) in a blood test result is broken down into Granulocytes (GRAN) and Lymphocytes (LYM).White blood cells are part of the immune system. An elevated level of granulocytes is indicative of a bacterial infection.he White Blood Count (WBC) in a blood test result is broken down into Granulocytes (GRAN) and Lymphocytes (LYM).