clearance

American  

[kleer-uhns] / ˈklɪər əns /

noun

1. the act of clearing.

2. the distance between two objects; an amount of clear space.

   The bridge allowed a clearance of 37 feet at mean high water.

3. a formal authorization permitting access to classified information, documents, etc.

4. Also called clearance sale.  the disposal of merchandise at reduced prices to make room for new goods.

   He bought the coat for half price at a clearance.

5. a clear space; a clearing.

   The house stood in a clearance among the trees.

6. Banking. an exchange of checks and other commercial paper drawn on members of a clearinghouse, usually effected at a daily meeting of the members.

7. Machinery. a space between two moving parts, left to avoid clashing or to permit relatively free motion.

8. the angle between a face of a cutting tool, as a lathe tool, and the work.

9. Nautical.

   1. the clearing of a ship at a port.

   2. Also called clearance papers.  the official papers certifying this.

10. Medicine/Medical. a test of the excretory function of the kidneys based on the volume of blood that is cleared of a specific substance per minute by renal excretion.

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clearance British  

/ ˈklɪərəns /

noun

1. 1. the process or an instance of clearing

      slum clearance

   2. ( as modifier )

      a clearance order

2. space between two parts in motion or in relative motion

3. permission for an aircraft, ship, passengers, etc, to proceed

4. official permission to have access to secret information, projects, areas, etc

5. banking the exchange of commercial documents drawn on the members of a clearing house

6. 1. the disposal of merchandise at reduced prices

   2. ( as modifier )

      a clearance sale

7. sport

   1. the act of hitting or kicking a ball out of the defensive area, as in football

   2. an instance of this

8. the act of clearing an area of land of its inhabitants by mass eviction See Highland Clearances

9. dentistry the extraction of all of a person's teeth

10. a less common word for clearing

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Other Word Forms

• nonclearance
  noun
• preclearance
  noun
• self-clearance
  noun

Etymology

Origin of clearance

First recorded in 1555–65; clear + -ance

Example Sentences

By influencing how these receptors move and function, the nanoparticles improved amyloid-β clearance and helped restore healthier blood vessel activity in the brain.

From Science Daily • May 17, 2026

Secretary of Defense Pete Hegseth has recently questioned his security clearance too.

From Slate • May 15, 2026

Three patients had complete tumor clearance and the majority of responders saw more than 50% tumor shrinkage.

From Barron's • May 11, 2026

Sir Olly was removed from his post last month after it emerged he had not told Sir Keir he had granted Lord Mandelson security clearance despite officials raising security concerns.

From BBC • May 6, 2026

Strauss informed Oppenheimer that his security clearance was suspended and urged him to resign quietly from his AEC position.

From "Big Science" by Michael Hiltzik

Related Words

• approval
• authorization
• consent
• go ahead
• green light