the outer limits or edge of an area or object
外围,边缘
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new buildings on the periphery of the hospital site .医院外围的新建筑。
 
a marginal or secondary position in, or part or aspect of, a group, subject, or sphere of activity
次要部分(或职位、方面),无关紧要的职位(或部分、方面)
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a shift in power from the centre to the periphery .权力从中心到边缘的转移。
 
"late 16th cent. (denoting a line that forms the boundary of something):  via late Latin from Greek