The ultimate plastic bottles (4)

I believe the answer is:

last

'the ultimate' is the definition.
(thesaurus)

'plastic bottles' is the wordplay.
'bottles' indicates a hidden word (bottling is a kind of containing).
'LAST' is hidden in the letters of 'plastic'.

(Other definitions for last that I've seen before include "nowhere near winning Miss World?" , "Least likely" , "Shoemaker's model" , "Continue" , "Final; endure" .)

I've seen this clue in The Telegraph.

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