Prefer to clad church in glass (8)
I believe the answer is:
schooner
'glass' is the definition.
(I know that schooner is a type of glass)
'prefer to clad church' is the wordplay.
'prefer to' becomes 'sooner' (I am not sure about this - if you are sure you should believe this answer much more).
'clad' is an insertion indicator (clad can mean covered by).
'church' becomes 'ch' (abbreviation on maps etc).
'sooner' placed around 'ch' is 'SCHOONER'.
'in' is the link.
Can you help me to learn more?
(Other definitions for schooner that I've seen before include "In the main it is" , "Sailing vessel - drinking vessel" , "A measure or glass for sherry" , "Sailing vessel used in former times" , "Type of glass" .)