Nostalgic style
I believe the answer is:
retro
'nostalgic style' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for retro that I've seen before include "Imitating a style from the recent past" , "sort of rocket" , "Reminiscent of a past style" , "Looking back" , "In a backward-looking style" .)