Side by side a bishop, rook — direction to follow (7)
I believe the answer is:
abreast
'side by side' is the definition.
(synonyms)
'a bishop rook direction to follow' is the wordplay.
'bishop' becomes 'B' (chess abbreviation).
'rook' becomes 'R' (chess abbreviation).
'direction' becomes 'east' (compass direction).
'to follow' is a charade indicator (letters next to each other) (some letters go after or follow others).
'a'+'b'+'r'+'east'='ABREAST'
(Other definitions for abreast that I've seen before include "acquainted" , "Side by side - in the picture" , "Well-informed" , "to be up to date" , "Alongside one another and facing the same way" .)