Oil n. : Any one of a great variety of unctuous combustible substances, not miscible with water; as, olive oil, whale oil, rock oil, etc. They are of animal, vegetable, or mineral origin and of varied composition, and they are variously used for food, for solvents, for anointing, lubrication, illumination, etc. By extension, any substance of an oily consistency; as, oil of vitriol.

Oil v. t. : To smear or rub over with oil; to lubricate with oil; to anoint with oil.

Example:
What kind of Oil to use on a squeaky wood chair?

Taxonomy
oils, mineral oils, substances, underground, vegetable oils, free encyclopedia, Petrochemicals, Fuel, petroleum, Food oils, lipids, Sulfuric acid, Animal fat, asphalt, modern times, foods, biodiesel, vitriolic.

Defination from the web:
oil is a substance that is in a viscous liquid state ("oily") at ambient temperatures or slightly warmer, and is both hydrophobic (immiscible ... Oil is a somewhat vague term to use chemically, and the scientific term for oils, fats, waxes, cholesterol and other oily substances found in ...