Willingly again taking on the daily grind (7)
I believe the answer is:
readily
'willingly' is the definition.
(I've seen this before)
'again taking on the daily grind' is the wordplay.
'again' becomes 're' (prefix meaning 'again').
'taking on' means one lot of letters go next to another.
'grind' is an anagram indicator (I've seen 'grinding' mean this (letters must be ground into a new form)).
'daily' anagrammed gives 'adily'.
're'+'adily'='READILY'
(Other definitions for readily that I've seen before include "Promptly; willingly" , "Willingly, quickly" , "Willingly, without reluctance" , "Without much difficulty" , "With pleasure" .)