Orderly getting terribly hot involving drugs outside (10)
I believe the answer is:
methodical
'orderly' is the definition.
(I've seen this before)
'terribly hot involving drugs outside' is the wordplay.
'terribly' indicates anagramming the letters.
'involving drugs' becomes 'medical' (I can't explain this - if you can you should give a lot more credence to this answer).
'outside' is an insertion indicator.
'hot' with letters rearranged gives 'tho'.
'tho' going into 'medical' is 'METHODICAL'.
'getting' acts as a link.
Can you help me to learn more?
(Other definitions for methodical that I've seen before include "Systematic" , "Orderly" , "following a set pattern" .)