Goodbye for irregular research fellow avoiding chores somehow (8)
I believe the answer is:
farewell
'goodbye' is the definition.
(I've seen this before)
'research fellow avoiding chores somehow' is the wordplay.
'avoiding' suggests deleting specific letters.
'somehow' is an anagram indicator.
'research'+'fellow'='researchfellow'
'researchfellow' with 'chores' taken away is 'earfellw'.
'earfellw' anagrammed gives 'FAREWELL'.
'for irregular' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
(Other definitions for farewell that I've seen before include "Cape at the southernmost point of Greenland" , "Goodbye, hope you get on" , "vale" , "It may be said when 15" , "Valedictory word" .)