Downtime Alison arranged in flat (3-11)

I believe the answer is:

two-dimensional

'flat' is the definition.
(thesaurus)

'downtime alison arranged' is the subsidiary indication.
'arranged' is an anagram indicator.
'downtime'+'alison'='downtimealison'
'downtimealison' with letters rearranged gives 'twodimensional'.

'in' is the link.

(Another definition for two-dimensional that I've seen is " shallow".)

I've seen this clue in The Independent.

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