Waiting to pick up diamonds, a feature of bridge (7)
I believe the answer is:
bidding
'a feature of bridge' is the definition.
I can't judge whether this definition defines the answer.
'waiting to pick up diamonds' is the wordplay.
'waiting' becomes 'biding'.
'to pick up' is an insertion indicator.
'diamonds' becomes 'd' (abbreviation in bridge say).
'biding' placed around 'd' is 'BIDDING'.
Can you help me to learn more?
(Other definitions for bidding that I've seen before include "Offering at auction" , "Activity of bridge players" , "(At one's) command" , "Commanding or make an offer at auction" .)