Cushion Brown left in Oman, possibly (8)
I believe the answer is:
insulate
'cushion' is the definition.
(thesaurus)
'brown left in oman possibly' is the wordplay.
I cannot quite see how this works, but
'left' could be 'l' (common abbreviation) and 'l' is located in the answer.
'in' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for insulate that I've seen before include "Cover something to prevent loss of heat" , "Thermally protect" , "Protect from heat, cold, noise etc" , "Lean suit (anag.)" , "Lag" .)