Brownish gray (5)
I believe the answer is:
'brownish gray' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for taupe that I've seen before include "Brownish-grey colour" , "Grey tinged with brown" , "Fifty Shades of Grey must include this" , "Greyish brown" , "Grey-brown colour" .)