The most common and most likely answer to this crossword clue is the 9 letter word CLEARANCE
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More clues leading to the result CLEARANCE
- Green light in spare room
- Cereal can go rotten in space
- Opportunity French finally lost to keep king in authority
- Space and opportunity to replace Henry with tragic king
- In brief drop, royal character getting permission to fly
- Permission for demolition
- Eviction, malignancy mostly involving tragic monarch
- Clubs find out about a church blessing
- Complete article on church evacuation
- Gap: “Everything Must Go!”
Buddy explains!

The straight part
We know that "authorization" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case authorization = clearance.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CLEARANCE mean?
CLEARANCE noun- The act of clearing or something (such as a space) cleared
- The distance between two moving objects, especially between parts of a machine
- The height or width of a tunnel, bridge or other passage, or the distance between a vehicle and the walls or roof of such passage; a gap, headroom.
- A permission for a vehicle to proceed, or for a person to travel.
- A permission to have access to sensitive or secret documents or other information.
- A permission to use something, usually intellectual property, that is legally, but not otherwise, protected.
- (retail) A sale of merchandise, especially at significantly reduced prices in order to make room for new merchandise or updated versions of the same merchandise.
- The settlement of transactions involving securities or means of payment such as checks by means of a clearing house.
- The removal of harmful substances from the blood; renal clearance.
- The act of potting all the remaining balls on a table at one visit.
- The act of kicking a ball away from the goal one is defending.
- Removal of pieces from a rank, file or diagonal so that a bishop, rook or queen is free to move along it.
- Clear or net profit.
- The first disposal in a chain that leaves the area of a stoppage, or a disposal that leaves the area of a stoppage itself.
- The act of leaving the area of a stoppage.