Musk enveloping a revolutionary is rank (7)
I believe the answer is:
echelon
'is rank' is the definition.
(I've seen this before)
'musk enveloping a revolutionary' is the wordplay.
'musk' becomes 'Elon' (Elon Musk).
'enveloping' is an insertion indicator.
'a revolutionary' becomes 'che' (Che Guevara the Marxist revolutionary).
'elon' going around 'che' is 'ECHELON'.
(Other definitions for echelon that I've seen before include "Echo Len (anag.)" , "Ladder formation" , "Level of people in organisation" , "Body of troops arranged in a line" , "Military formation; level of society" .)