door ‧ stop /ˈdɔːstɒp $ ˈdɔːrstɑːp/ BrE AmE ( also door‧stop‧per /-ˌstɒpə $ -ˌstɑːpər/ British English ) noun [countable]
1 . something you put under or against a door to keep it open
2 . a rubber object fastened to a wall to stop a door hitting it when it opens