(ŏkʹtān´) noun. Any of various isomeric paraffin hydrocarbons with the formula C8H18, found in petroleum and used as a fuel and solvent, oktana.
octane number (ŏkʹtĀn´ nŭmʹbər) noun. A numerical representation of the antiknock properties of motor fuel, compared with a standard reference fuel, such as isooctane, which has an octane number of 100. Also called
octane rating, nombor oktana.