ortho-xylene

ortho-xylene

[¦ȯr·thō ′zī‚lēn] (organic chemistry) 1,2-C6H4(CH3)2 A flammable, moderately toxic liquid; insoluble in water, soluble in alcohol and ether; boils at 144°C; used to make phthalic anhydride, vitamins, pharmaceuticals, and dyes, and in insecticides and motor fuels.