Supply revamped course put on outside (8)
I believe the answer is:
resource
'supply' is the definition.
(thesaurus)
'revamped course put on outside' is the wordplay.
I cannot quite see how this works, but
an anagram of 'course' is 'esourc' which is present in the answer.
'on' could be 're' ('on' can be mean 'with reference to') and 're' is located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for resource that I've seen before include "From which help can be obtained" , "Source of help" , "Means of help in project" , "Reserve to draw upon when needed" , "Anything that's there to assist when needed" .)