Blood? Good Lord (4)

I believe the answer is:

king

'lord' is the definition.

'blood? good' is the wordplay.
'blood?' becomes 'kin' (blood is a kind of kin).
'good' becomes 'g' (abbreviation).
'kin'+'g'='KING'

(Other definitions for king that I've seen before include "Card, draughts piece" , "US civil rights leader, assassinated 1968" , "as Solomon was" , "Honour for man" , "Recipient of 10 21 [VELODROME GOLD]" .)

I've seen this clue in The Sunday Times.

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