Crossword Genius

Show yellow card to reserve (4)

Ross

I believe the answer is:

book

I believe this clue is a double definition.

'show yellow card' is the first definition.
(booking a footballer is showing them a yellow card)

'to reserve' is the second definition.
(to book something is to reserve it)

(Other definitions for book that I've seen before include "Tome, volume" , "Reserve - something to read" , "Volume - maybe thrown at offender" , "Make a reservation" , "Reading volume" .)

I've seen this clue in The Guardian and The Telegraph.
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