Purple: the mast after rigging containing hint of yellow (8)
I believe the answer is:
amethyst
'purple' is the definition.
(thesaurus)
'the mast after rigging containing hint of yellow' is the wordplay.
'after rigging' is an anagram indicator (a distorted or rigged spelling).
'containing' indicates putting letters inside.
'hint of' indicates taking the first letters.
The initial letter of 'yellow' is 'y'.
'the'+'mast'='themast'
'themast' anagrammed gives 'amethst'.
'amethst' going around 'y' is 'AMETHYST'.
(Other definitions for amethyst that I've seen before include "February stone" , "Violet gemstone" , "A Middle East language" , "One showing sparkling facets" , "February gemstone" .)