Passion of Dior ultimately found within vintage Vogue covers (5)
I believe the answer is:
verve
'passion' is the definition.
(thesaurus)
'dior ultimately found within vintage vogue covers' is the wordplay.
'ultimately' says to take the final letters.
'found within' means one lot of letters goes inside another.
'vintage' becomes 've' (I can't explain this - if you can you should believe this answer much more).
'covers' says to hollow out the word (remove centre letters) (I've seen 'covering' mean this (the letters which cover the word are used)).
'vogue' with its centre removed is 've'.
The final letter of 'dior' is 'r'.
've'+'ve'='veve'
'r' inserted within 'veve' is 'VERVE'.
'of' is the link.
(Other definitions for verve that I've seen before include "Animation" , "Energy and zest" , "Dashing enthusiasm" , "Zest and exuberance" , "Vigour, spirit, style" .)