A technical dictionary of printmaking, André Béguin.

abietic acid , abietinic acid
Major active ingredient of rosin, where it occurs with other acids of closely related structures and properties, i.e. the resin acids. The term is often applied to these mixtures.
It is a yellow resinous powder, soluble in aclohol, ether, chloroform and benzene, insoluble in water, Formula: C19H29COOH.