A series in which to succeed (5)

I believe the answer is:

order

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'a series' is the definition.
(thesaurus)

I don't understand the remainder of the clue.

(Other definitions for order that I've seen before include "an answer to all clues, initially" , "Tell - regulate" , "Command or written direction" , "Select from menu" , "Instruct" .)

I've seen this clue in the Evening Standard.

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