gate  
noun [ C ] uk/ɡeɪt/ us/ɡeɪt/
  (STRUCTURE)           
 A2 (通常由金属条或木头条板做的)大门,栅栏门,围墙门
a part of a fence or outside wall that is fixed at one side and opens and closes like a door, usually made of metal or wooden strips
  (可滑动伸缩的)推拉门,活动门,卷帘门
a similar device that slides across an opening, often folding into a smaller space as it is opened
  The lift won't move if the safety gate isn't shut properly. 如果防护门没有关好,电梯不会开动。 
 B1 (机场大楼的)登机门,登机口
a part of an airport where travellers are allowed to get on or off a particular aircraft
  All passengers for flight LH103 please proceed to gate 16. 搭乘 LH103次班机的乘客请前往16号登机口登机。 
 - More examples
 - The paths all converge at the main gate of the park.
 - The sign on the gate said 'Private Property - No Admittance.'
 - Passengers for Madrid should proceed to gate 26 for boarding.
 - Please shut the gate.
 - An angry crowd surged through the gates of the president's palace.
 
  (PEOPLE)      
 UK informal观众人数;门票收入 
the number of people that go to see a sports event or other large event, or the amount of money people pay to see it
  Gates at matches were lower than average last season. 上个赛季观看足球比赛的人数低于平均水平。