A familiar piece of a charger (8)
I believe the answer is:
warhorse
'a familiar' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'piece of a charger' is the wordplay.
'piece of' becomes 'war' (I can't explain this - if you can you should believe this answer much more).
'a charger' becomes 'horse' (I've seen this before).
'war'+'horse'='WARHORSE'
Can you help me to learn more?
(Other definitions for warhorse that I've seen before include "something too often played" , "steed?" , "Veteran soldier" , "Belligerent" , "Old soldier" .)