clearance noun
1 removal of sth old/unwanted
ADJ. forest, land, site, slum
CLEARANCE + NOUN work | sale (= in a shop when goods are sold cheaply to get rid of them quickly)
2 official permission
ADJ. official | customs, diplomatic, entry, security
VERB + CLEARANCE get, obtain, receive You'll need to get security clearance for this job. | apply for, seek | give sb, grant sb The pilot was granted clearance to land. | refuse sb
3 distance between sth and sth passing under/beside it
ADJ. ground We need to increase the vehicle's ground clearance.
VERB + CLEARANCE allow (sb/sth), give sb/sth, leave Make sure you allow enough clearance on each side. Always give cyclists plenty of clearance.
PREP. ~ above clearance above the light to prevent overheating | ~ between There wasn't enough clearance between the bus and the top of the bridge.
You can also check other dicts: clearance (English, 中文解释 ), wordnet sense, Collins Definition