Rather tangled noose on revolutionary leader (6)
I believe the answer is:
sooner
'rather' is the definition.
('I'd sooner do that' means 'I'd rather do that')
'tangled noose on revolutionary leader' is the wordplay.
'tangled' is an anagram indicator.
'on' means one lot of letters go next to another.
'leader' suggests taking the first letters.
The initial letter of 'revolutionary' is 'r'.
'noose' anagrammed gives 'soone'.
'soone'+'r'='SOONER'
(Other definitions for sooner that I've seen before include "At an earlier time" , "native of Oklahoma" , "nickname of US State" , "Earlier; more willingly" , "Earlier or preferably" .)