Vessel seen earlier outside church (8)
I believe the answer is:
schooner
'vessel' is the definition.
(type of ship)
'earlier outside church' is the wordplay.
'earlier' becomes 'sooner' (synonyms).
'outside' is an insertion indicator (some letters go outside others).
'church' becomes 'ch' (abbreviation on maps etc).
'sooner' enclosing 'ch' is 'SCHOONER'.
'seen' is the link.
(Other definitions for schooner that I've seen before include "Measure for sherry or kind of sailing ship" , "Old sailing vessel and large glass" , "In the main it is" , "Two-masted sailing ship" , "No chores on this sailing ship" .)