nosy parker
From Longman Dictionary of Contemporary Englishnosy parkerˌnosy ˈparker noun [countable] British English informal FIND OUTsomeone who is too interested in finding out about other people’s affairs – used to show disapprovalExamples from the Corpusnosy parker• He was also branded a nosy parker by some of his Abingdon neighbours.• We don't need an extra nosy parker round here.