[1] : The Collaborative International Dictionary of English v.0.48

undoer \undo"er\, n.
   one who undoes anything; especially, one who ruins another.
   1913 webster

[2] : WordNet (r) 2.0

undoer
     n 1: a seducer who ruins a woman; "she awoke in the arms of her
          cruel undoer"
     2: a person who unfastens or unwraps or opens; "children are
        talented undoers of their shoelaces" syn: opener, unfastener,
         untier
     3: a person who destroys or ruins or lays waste to; "a
        destroyer of the environment"; "jealousy was his undoer";
        "uprooters of gravestones" syn: destroyer, ruiner, waster,
         uprooter
see also:
opener unfastener untier destroyer ruiner waster 
uprooter 

Undoer >> U Words
Undoer, definition of term: Undoer
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