Feed stranger after first of friends (6)
I believe the answer is:
fodder
'feed' is the definition.
(fodder is a kind of feed)
'stranger after first of friends' is the wordplay.
'stranger' becomes 'odder' (I've seen this before).
'after' means one lot of letters go next to another.
'first of' indicates taking the first letters.
The initial letter of 'friends' is 'f'.
'odder' after 'f' is 'FODDER'.
(Other definitions for fodder that I've seen before include "Dried food like hay for horses" , "Food for livestock" , "Animal feed" , "Food for horses or cattle" , "Straw to eat" .)