mindmap root((边界)) border refers to the part of a surface just within a boundary: magazine cover’s red ~; or the boundary itself: across international ~s. margin denotes a border or definite width or distinguishing character: a ~ of one inch on the page’s left side. verge applies to the line marking an extreme limit or termination of something: an empire that extended to the ~ of the known world. edge denotes the line of termination made by two converging surfaces as of a blade or a box: the ~ of the table. rim applies to an edge of something circular or curving: the ~ of a wagon wheel. brim applies to the upper inner rim of something hollow: fill the cup to the ~. brink denotes the edge of something that falls away steeply: walked to the ~ of the cliff; and may imply abrupt transition: nations on the ~ of peace.