Feature covering a series (5)
I believe the answer is:
chain
'series' is the definition.
(I know that chain is a type of series)
'feature covering a' is the wordplay.
'feature' becomes 'chin' (facial feature).
'covering' means one lot of letters goes inside another.
'chin' going around 'a' is 'CHAIN'.
(Other definitions for chain that I've seen before include "Handcuff" , "Fetter" , "a sort of letter" , "Line of links" , "Rope of metal links" .)