WEBaxis uk / ˈæk.sɪs/ us / ˈæk.sɪs/ noun. a real or imaginary straight line going through the centre of a object that is spinning, or a line that divides a symmetrical shape into two equal halves: The earth revolves around the axis that joins the North and South Poles. 地球围绕贯穿南北两极的地轴自转。.