Base fellow essentially mainlining wine (8)
I believe the answer is:
heliport
'base' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'fellow essentially mainlining wine' is the wordplay.
'fellow' becomes 'he' ('he' refers to a man).
'essentially' says to take the centre.
'wine' becomes 'port' (port wine is a kind of wine).
The middle letters of 'mainlining' are 'li'.
'he'+'li'+'port'='HELIPORT'
Can you help me to learn more?
(Other definitions for heliport that I've seen before include "landing platform" , "Home for choppers?" , "Site for vertical take-off" , "where choppers may rest" , "Landing-place" .)