Choice bishop makes directly (5)
I believe the answer is:
plumb
'directly' is the definition.
(thesaurus)
'choice bishop' is the wordplay.
'choice' becomes 'plum ' (I've seen this before).
'bishop' becomes 'B' (abbreviation used in chess).
'plum'+'b'='PLUMB'
'makes' acts as a link.
(Other definitions for plumb that I've seen before include "Precisely" , "Weight to show vertical direction" , "Check depth of water below" , "Take soundings at sea" , "Measure the depth of water" .)