|fēō+ noun
also pheo·chro·mo·cy·to·blast ˌfēōˌkrōmōˈsīd.əˌblast
Etymology: pheochromoblast from pheochrome + -o- + -blast; pheochromocytoblast from pheochromocyte + -o- + -blast
: an embryonic cell destined to give rise to chromaffin tissue especially of the adrenal medulla