Being lazy, lacks organisation (5)

I believe the answer is:

slack

'being lazy' is the definition.
(thesaurus)

'lacks organisation' is the wordplay.
'organisation' indicates anagramming the letters.
'lacks' is an anagram of 'SLACK'.

(Other definitions for slack that I've seen before include "Loose" , "skive" , "Not taut" , "Limp - negligent" , "Powdery coal" .)

I've seen this clue in the Evening Standard.

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