sector
/ˈsektə(r); `sɛktɚ/ n
1 part of a circle lying between two straight lines drawn from the centre to the circumference 扇形. => illus at circle 见 circle 插图.
2 part or branch of a particular area of activity, esp of a country's economy （活动领域的）部门; （尤指）经济领域
the manu`facturing sector, ie all the manufacturing industries of a country 制造业
the `service sector, eg hotels, restaurants, etc 服务性行业.
3 any of the parts of a battle area, or of an area under military control 战区; 防区
an enemy attack in the southern sector 敌军对南部战区的进攻.