All but meaning to regulate press (9)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
importune
'press' is the definition.
(thesaurus)
'all but meaning to' is the wordplay.
'all but' means to remove the last letter ('all but' can mean 'almost' or 'nearly').
'meaning' becomes 'import' (synonyms).
'to' becomes 'tune' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'import' with its final letter taken away is 'impor'.
'impor'+'tune'='IMPORTUNE'
'regulate' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for importune that I've seen before include "press to give answers" , "Harrass with persistent requests" , "Harass" , "badger" , "Solicit" .)