Extremely agitated groom gives speech (7)
I believe the answer is:
Here is my best explanation:
'speech' is the definition.
(address is a kind of speech)
'extremely agitated groom' is the subsidiary indication.
'extremely' means to remove the middle letters.
'groom' becomes 'dress' (dressing is a kind of grooming).
'agitated' with its centre taken out is 'ad'.
'gives' is the link.
(Other definitions for address that I've seen before include "Discourse", "Place where someone lives", "Talk - indication of house", "skilfulness or tact", "Think about", "Form of identification for building", "Speak formally to an audience", "Speak to, approach", "details on envelope" and "place".)