Wanted to dump man in fact (4)
I believe the answer is:
deed
'fact' is the definition.
(thesaurus)
'wanted to dump man' is the wordplay.
I cannot really see how this works, but
'man' could be 'ed' (short for Edward) and 'ed' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'in' is the link.
Can you help me to learn more?
(Other definitions for deed that I've seen before include "documentary evidence" , "Something done" , "Heroic exploit" , "Document showing ownership" , "Intentional action" .)