revolving door

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. an organization or institution with a high rate of turnover of personnel or membership
• Hypernyms:
social group
2. a door consisting of four orthogonal partitions that rotate about a central pivot;
a door designed to equalize the air pressure in tall buildings
• Syn:
revolver
• Hypernyms:
door