Green’s Dictionary of Slang

to beat, to assault; to box; thus milvadering n., a set-to, a fight, a boxing-match.

1821		D. Haggart Autobiog. 33: Barney struck him, I joined in, and a terrible milvadering took place.
1824		Annals of Sporting 1 Feb. 120: Let us see [...] if his opponent do not own lushing in a budge-kain sport quite as easy as the milvadering he is engaged in .
1834		‘Jack Downing’ Andrew Jackson 38: A long spell of catterclawin and milvaderin.
1864, 1867, 1870		Hotten Sl. Dict.