Direct answer: Distilled tar usually means tar that has been heated and separated into fractions, or a tar product obtained through destructive distillation of organic material.
The wording can be confusing because tar itself is often made by destructive distillation, while tar can also be distilled again to separate oils, pitches, creosote fractions, and other products. In older technical writing, “distilled tar” may refer to either stage.
Distilled tar belongs to industrial chemistry, wood-tar creosote, coal-tar products, tar oils, and pitch making. It helps explain how a crude black liquid becomes multiple commercial materials rather than one uniform substance.
Raw tar is the mixed product from a kiln, retort, coke oven, or similar process. Distilled tar or tar distillate points toward later separation. The exact meaning depends on the industry.
In short: Tar can be produced by destructive distillation. Crude tar can also be re-distilled into fractions. Distillation can yield oils, creosote fractions, and pitch residues. The phrase is context-dependent.