150 say 'What an untidy mess!' (7)

I believe the answer is:

clutter

'what an untidy mess' is the definition.
(I've seen this before)

'150 say' is the wordplay.
'150' becomes 'CL' (roman numerals).
'say' becomes 'utter' (to utter something is to speak or say it).
'cl'+'utter'='CLUTTER'

(Other definitions for clutter that I've seen before include "Untidy lot of objects in room" , "Untidy accumulation of objects" , "Things lying about untidily" , "Jumble" , "Untidiness" .)

I've seen this clue in The Irish Independent.

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