Caledonian taking an article from the racecourse (4)
I believe the answer is:
scot
'caledonian' is the definition.
(I've seen this before)
'an article from the racecourse' is the wordplay.
'an article' becomes 'a' (indefinite article).
'from' is a deletion indicator.
'the racecourse' becomes 'ascot' (I've seen this before).
'ascot' with 'a' taken out is 'SCOT'.
'taking' is the link.
(Other definitions for scot that I've seen before include "Jock?" , "North Briton" , "Northern member of UK" , "Native of northern Great Britain" , "Eg Aberdonian" .)