Correct spelling for the English word "Borcer" is [bˈɔːsə], [bˈɔːsə], [b_ˈɔː_s_ə] (IPA phonetic alphabet).
An instrument for boring holes in large rocks in order to blow them up.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.