- 1the outer edge of a particular area industrial development on the periphery of the town The condition makes it difficult for patients to see objects at the periphery of their vision. Extensive new planting is taking place around the periphery of the site.
- 2the less important part of something, for example of a particular activity or of a social or political group minor parties on the periphery ofAmerican politics
NAmE//pəˈrɪfəri//[usually singular](pl. peripheries)(formal)