Modest form of sachet (6)

I believe the answer is:

chaste

'modest' is the definition.
(thesaurus)

'form of sachet' is the wordplay.
'form of' is an anagram indicator (the letters need to be in another 'form').
'sachet' is an anagram of 'CHASTE'.

(Other definitions for chaste that I've seen before include "Showing virtue of kind" , "Refraining from sex" , "Untouched ..." , "Everlasting" , "Innocent" .)

I've seen this clue in the Evening Standard.

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