Of, relating to, or located within the limits or surface; inner. Residing in or dependent on essential nature; intrinsic: the internal contradictions of the theory. Located, acting, or effective within the body. Of or relating to mental or spiritual nature: "An internal sense of righteousness dwindles into an external concern for reputation\u201d ( A.R. Gurney, Jr.) Of or relating to the domestic affairs of a nation, group, or business.