Determination to work out again (7)
I believe the answer is:
resolve
'determination' is the definition.
(I've seen this in another clue)
'work out again' is the wordplay.
I cannot really understand how this works, but
'work' could be 'solve' (synonyms) and 'solve' is found in the answer.
'again' could be 're' (prefix meaning 'again') and 're' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'to' acts as a link.
Can you help me to learn more?
(Other definitions for resolve that I've seen before include "Fix" , "Make a firm decision" , "Determine firmly" , "break up" , "Settle (a matter)" .)