Rub lead in dead skin (4)
I believe the answer is:
rind
'skin' is the definition.
(synonyms)
'rub lead in dead' is the wordplay.
'lead' indicates taking the first letters.
'dead' becomes 'd' (abbreviation in government records).
The initial letter of 'rub' is 'r'.
'r'+'in'+'d'='RIND'
(Other definitions for rind that I've seen before include "Hard outer skin, of an orange say" , "Fruit covering" , "outside" , "Skin of orange or melon" , "Outer skin of citrus fruit" .)