Tacky – A descriptive term applied to greases which are particularly sticky or cohesive.

Tallow – Animal fat prepared from beef and mutton.

Thermal Conductivity – Measure of the ability of a solid or liquid to transfer heat.

TOST – Turbine Oil Stability Test, ASTM D-943

Total Acid Number (TAN) – The quantity of base, expressed in milligrams of potassium hydroxide, that is required to titrate all acidic constituents present in 1 gram of sample.

Total Base Number (TBN) – The quantity of base, expressed in terms of the equivalent number of milligrams of potassium hydroxide, that is required to titrate all basic constituents present in 1 gram of sample.

Turbine Quality – Lube base stocks suitable for turbine applications, finished with severe hydrotreating. TQ base stocks exhibit improved oxidation stability over MQ base stocks.