Beginning to engrave lines on bishop's ring (4)
I believe the answer is:
bell
'ring' is the definition.
(both can mean to call on the phone)
'beginning to engrave lines on bishop's' is the wordplay.
'beginning to' suggests taking the first letters.
'lines' becomes 'll' (an abbreviation for line written twice).
'on' is a charade indicator (letters next to each other).
'bishop' becomes 'B' (chess abbreviation).
The first letter of 'engrave' is 'e'.
'e'+'ll'='ell'
'ell' after 'b' is 'BELL'.
(Other definitions for bell that I've seen before include "Metal instrument" , "bicycle accessory" , "It's struck by a hammer or clapper" , "inventive fellow" , "It rings when struck" .)