Some parcel trotted out for old Brit (4)
I believe the answer is:
celt
'old brit' is the definition.
(I've seen this in another clue)
'some parcel trotted out' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'CELT' is hidden within 'parcel trotted out'.
'for' is the link.
(Other definitions for celt that I've seen before include "Ancient Briton" , "one who spoke Manx, for example" , "Early Briton" , "Early European" , "Pre-Roman inhabitant of Ireland and Britain" .)