Praise dropping a train network for non-union shenanigans (8)
I believe the answer is:
adultery
'non-union shenanigans' is the definition.
(union can mean a marriage)
'praise dropping a train network' is the wordplay.
I cannot really see how this works, but
'a' is present in the answer.
'train network' could be 'ry' (abbreviation for railway) and 'ry' is found within the answer.
This explanation may well be incorrect...
'for' is the link.
(Other definitions for adultery that I've seen before include "Seventh Commandment infraction" , "Act of infidelity by husband or wife" , "cheating" , "Extramarital sex" , "Affairs" .)