orbital
/ˈɔ:bɪtl; `ɔrbɪtl/ adj
of an orbit （星体的或人造飞行物体的）轨道的; 势力范围的
a spacecraft's orbital distance from the earth 航天器的远地轨道距离
an orbital motorway, ie round the outside of a city 外环高速公路. -- n road passing round the outside of a city （城市的）外环路
Take the London orbital. 走伦敦外环路.