The Collaborative International Dictionary of English v.0.48:
Botch \Botch\, n.; pl. Botches. [Same as Boss a stud. For
senses 2 & 3 cf. D. botsen to beat, akin to E. beat.]
1. A swelling on the skin; a large ulcerous affection; a
boil; an eruptive disease. [Obs. or Dial.]
Botches and blains must all his flesh emboss.
2. A patch put on, or a part of a garment patched or mended
in a clumsy manner.
3. Work done in a bungling manner; a clumsy performance; a
piece of work, or a place in work, marred in the doing, or
not properly finished; a bungle.
To leave no rubs nor botches in the work. --Shak.