1. [n]  oil paint used by an artist
2. [n]  a slippery or viscous liquid or liquefiable substance not miscible with water
3. [v]  administer an oil or ointment to ; often in a religious ceremony of blessing
4. [v]  cover with oil, as if by rubbing; "oil the wooden surface"

1. \Oil\ (oil), n. [OE. oile, OF. oile, F. huile, fr. L. oleum;
   akin to Gr. ?. Cf. {Olive}.]
   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.
   
   Note: The mineral oils are varieties of petroleum. See
         {Petroleum}. The vegetable oils are of two classes,
         {essential oils} (see under {Essential}), and {natural
         oils} which in general resemble the animal oils and
         fats. Most of the natural oils and the animal oils and
         fats consist of ethereal salts of glycerin, with a
         large number of organic acids, principally stearic,
         oleic, and palmitic, forming respectively stearin,
         olein, and palmitin. Stearin and palmitin prevail in
         the solid oils and fats, and olein in the liquid oils.
         Mutton tallow, beef tallow, and lard are rich in
         stearin, human fat and palm oil in palmitin, and sperm
         and cod-liver oils in olein. In making soaps, the acids
         leave the glycerin and unite with the soda or potash.
   
   {Animal oil}, {Bone oil}, {Dipple's oil}, etc. (Old Chem.), a
      complex oil obtained by the distillation of animal
      substances, as bones. See {Bone oil}, under {Bone}.
   
   {Drying oils}, {Essential oils}. (Chem.) See under {Drying},
      and {Essential}.
   
   {Ethereal oil of wine}, {Heavy oil of wine}. (Chem.) See
      under {Ethereal}.
   
   {Fixed oil}. (Chem.) See under {Fixed}.
   
   {Oil bag} (Zo["o]l.), a bag, cyst, or gland in animals,
      containing oil.
   
   {Oil beetle} (Zo["o]l.), any beetle of the genus {Meloe} and
      allied genera. When disturbed they emit from the joints of
      the legs a yellowish oily liquor. Some species possess
      vesicating properties, and are used instead of
      cantharides.
   
   {Oil box}, or {Oil cellar} (Mach.), a fixed box or reservoir,
      for lubricating a bearing; esp., the box for oil beneath
      the journal of a railway-car axle.
   
   {Oil cake}. See under {Cake}.
   
   {Oil cock}, a stopcock connected with an oil cup. See {Oil
      cup}.
   
   {Oil color}.
   (a) A paint made by grinding a coloring substance in oil.
   (b) Such paints, taken in a general sense.
   
   
   
   {Oil cup}, a cup, or small receptacle, connected with a
      bearing as a lubricator, and usually provided with a wick,
      wire, or adjustable valve for regulating the delivery of
      oil.
   
   {Oil engine}, a gas engine worked with the explosive vapor of
      petroleum.
   
   
   
   {Oil gas}, inflammable gas procured from oil, and used for
      lighting streets, houses, etc.
   
   {Oil gland}.
   (a) (Zo["o]l.) A gland which secretes oil; especially in
       birds, the large gland at the base of the tail.
   (b) (Bot.) A gland, in some plants, producing oil.
   
   {Oil green}, a pale yellowish green, like oil.
   
   {Oil of brick}, empyreumatic oil obtained by subjecting a
      brick soaked in oil to distillation at a high temperature,
      -- used by lapidaries as a vehicle for the emery by which
      stones and gems are sawn or cut. --Brande & C.
   
   {Oil of talc}, a nostrum made of calcined talc, and famous in
      the 17th century as a cosmetic. [Obs.] --B. Jonson.
   
   {Oil of vitriol} (Chem.), strong sulphuric acid; -- so called
      from its oily consistency and from its forming the
      vitriols or sulphates.
   
   {Oil of wine}, [OE]nanthic ether. See under {[OE]nanthic}.
   
   {Oil painting}.
   (a) The art of painting in oil colors.
   (b) Any kind of painting of which the pigments are originally
       ground in oil.
   
   {Oil palm} (Bot.), a palm tree whose fruit furnishes oil,
      esp. {El[ae]is Guineensis}. See {El[ae]is}.
   
   {Oil sardine} (Zo["o]l.), an East Indian herring ({Clupea
      scombrina}), valued for its oil.
   
   {Oil shark} (Zo["o]l.)
   (a) The liver shark.
   (b) The tope.
   
   {Oil still}, a still for hydrocarbons, esp. for petroleum.
   
   {Oil test}, a test for determining the temperature at which
      petroleum oils give off vapor which is liable to explode.
   
   
   {Oil tree}. (Bot.)
   (a) A plant of the genus {Ricinus} ({R. communis}), from the
       seeds of which castor oil is obtained.
   (b) An Indian tree, the mahwa. See {Mahwa}.
   (c) The oil palm.
   
   {To burn the midnight oil}, to study or work late at night.
   
   
   {Volatle oils}. See {Essential oils}, under {Essential}.
   
   

2. \Oil\, v. t. [imp. & p. p. {Oiled}; p. pr. & vb. n.
   {Oiling}.]
   To smear or rub over with oil; to lubricate with oil; to
   anoint with oil.
   
   

1. ["The Architecture of the FAIM-1 Symbolic Multiprocessing System", A. Davis et al, 9th Intl Joint Conf in Artif Intell, 1985, pp.32-38].

2. Operator Identification Language. Used for overloading resolution by the eli compiler-writing system.

Only olive oil seems to have been used among the Hebrews. It was used for many purposes: for anointing the body or the hair (Ex. 29:7; 2 Sam. 14:2; Ps. 23:5; 92:10; 104:15; Luke 7:46); in some of the offerings (Ex. 29:40; Lev. 7:12; Num. 6:15; 15:4), but was excluded from the sin-offering (Lev. 5:11) and the jealousy-offering (Num. 5:15); for burning in lamps (Ex. 25:6; 27:20; Matt. 25:3); for medicinal purposes (Isa. 1:6; Luke 10:34; James 5:14); and for anointing the dead (Matt. 26:12; Luke 23:56).

It was one of the most valuable products of the country (Deut. 32:13; Ezek. 16:13), and formed an article of extensive commerce with Tyre (27:17).

The use of it was a sign of gladness (Ps. 92:10; Isa. 61:3), and its omission a token of sorrow (2 Sam. 14:2; Matt. 6:17). It was very abundant in Galilee. (See OLIVE.)