Definition of oversman in US English:

oversman

noun

Scottish
  • 1Law. An arbiter; specifically a person appointed to decide on the outcome of an arbitrated dispute where the arbiters previously appointed have been unable to agree on a settlement. Compare "overman").

  • 2Specifically. A foreman or supervisor in a mine or colliery.

Origin

Late 15th century. Alteration of overman, after genitive compounds in man, as e.g. doomsman, redesman, etc.