bone oil

noun

Definition of bone oil

1 : a dark-colored ill-smelling oil obtained by carbonizing bones (as in making bone black) that contains hydrocarbons and many nitrogen compounds (such as pyrrole and pyridine bases) and is used especially in sheep dips and in denaturing alcohol

called also animal oil, Dippel's oil

2 : the liquid portion of bone fat used as a lubricant and in leather manufacture