Bishop and American holding fork (6)
I believe the answer is:
branch
'fork' is the definition.
(I know that fork can be written as branch)
'bishop and american holding' is the wordplay.
'bishop' becomes 'B' (chess abbreviation).
'and' becomes 'n' (common abbreviation for 'and').
'american' becomes 'rach' (I can't explain this - if you can you should give a lot more credence to this answer).
'holding' means one lot of letters goes inside another.
'n' placed inside 'rach' is 'ranch'.
'b'+'ranch'='BRANCH'
Can you help me to learn more?
(Other definitions for branch that I've seen before include "Trunk offshoot" , "Bough - offshoot - secondary office" , "Arm" , "Fork of a main stem" , "Part of a tree; division" .)