Liquid material used for a coat? (8)
I believe the answer is:
emulsion
'a coat?' is the definition.
(emulsion is a kind of coat)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for emulsion that I've seen before include "Wall paint" , "Type of paint" , "Mixture involving two liquids which do not readily combine" , "Mixture of insoluble liquids" .)