1560s, "action of clearing," from clear (v.) + -ance. Meaning "a clear space" is from 1788. Meaning "approval, permission" (especially to land or take off an aircraft) is from 1944, American English; national security sense recorded from 1948. Clearance sale attested by 1843.
雙語例句
1. The UN pledged to help supervise the clearance of mines.
聯(lián)合國承諾協(xié)助監(jiān)督掃雷工作。
來自柯林斯例句
2. They have to wait for clearance from air traffic control.
他們需要等空中交通管制人員的放行。
來自柯林斯例句
3. He has a security clearance that allows him access to classified information.
他獲得了安全許可，可以接觸機密信息。
來自柯林斯例句
4. Thai Airways said the plane had been given clearance to land.