Ventured, again, to put father out (5)
I believe the answer is:
dared
'ventured' is the definition.
(I've seen this before)
'again to put father out' is the wordplay.
'again' becomes 're' (prefix meaning 'again').
'to put father' becomes 'dad' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'out' is an insertion indicator.
're' inserted into 'dad' is 'DARED'.
Can you help me to learn more?
(Other definitions for dared that I've seen before include "was bold enough" , "Acted with courage - or dread?" , "Was brave enough" , "Defied, challenged" , "Made bold" .)