Majority welcome editor on return, self-effacing (6)
I believe the answer is:
modest
'self-effacing' is the definition.
(I've seen this before)
'majority welcome editor on return' is the wordplay.
'majority' becomes 'most' (I've seen this before).
'welcome' indicates putting letters inside (in sense of 'inviting in').
'editor' becomes 'ed'.
'on return' says the letters should be written in reverse.
'ed' back-to-front is 'de'.
'most' enclosing 'de' is 'MODEST'.
(Other definitions for modest that I've seen before include "Mussorgsky, nominally?" , "Unassuming; limited" , "Native of Vienna" , "'Humble, unassuming (6)'" , "Free from pomp or affectation" .)