Orderly in quite a big way (4)

I believe the answer is:

tidy

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'orderly' is the definition.
(similar in meaning)

I don't understand how the rest of the clue works.

(Other definitions for tidy that I've seen before include "Shipshape" , "In apple-pie order" , "small container in which odds and ends are kept" , "Businesslike" , "Fairly big - orderly" .)

I've seen this clue in the Evening Standard.

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