Will try, having meant to give a whirl to (9)
I believe the answer is:
testament
'will' is the definition.
(synonyms)
'give a whirl to' is the wordplay.
'give a whirl' becomes 'test' (I've seen this in another clue).
'to' becomes 'ament' (I can't justify this - if you can you should give a lot more credence to this answer).
'test'+'ament'='TESTAMENT'
'try having meant to' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for testament that I've seen before include "Will - covenant" , "Scripture" , "books, with 1a [OLD]" , "evidence" , "Tribute" .)