Bring in a book of great significance (9)

I believe the answer is:

important

'of great significance' is the definition.
(I've seen this before)

'bring in a book' is the wordplay.
'bring in' becomes 'import' (I've seen this before).
'book' becomes 'nt' (I've seen this in other clues**).
'import'+'a'+'nt'='IMPORTANT'

(Other definitions for important that I've seen before include "major" , "Crucial" , "influential" , "material" , "Eminent" .)

I've seen this clue in The Telegraph.

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