Let bank arrange overall cover (7)

I believe the answer is:

blanket

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'overall cover' is the definition.
'blanket' can be an answer for 'cover' (synonyms). I am unsure of the 'overall' bit.

'let bank arrange' is the wordplay.
'arrange' is an anagram indicator.
'let'+'bank'='letbank'
'letbank' with letters rearranged gives 'BLANKET'.

Can you help me to learn more?

(Other definitions for blanket that I've seen before include "Comprehensive" , "Warm covering" , "coating" , "See 12" , "Bedcover" .)

I've seen this clue in The Globe and Mail.

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