Rook, leaving Bury, coming into Hull? It's telling (7)
I believe the answer is:
pointed
'telling' is the definition.
(thesaurus)
'rook leaving bury coming into hull?' is the wordplay.
'rook' becomes 'r' (abbreviation in chess).
'leaving' suggests deleting specific letters.
'bury' becomes 'inter' (synonyms).
'coming into' indicates putting letters inside.
'hull?' becomes 'pod' (I've seen this before).
'inter' with 'r' removed is 'inte'.
'inte' going inside 'pod' is 'POINTED'.
'it's' is the link.
(Other definitions for pointed that I've seen before include "Direct and obvious in meaning" , "Sharp-ended" , "Aculeate" , "keen" , "Of remark, direct and cutting" .)