Phenyl silicone fluid, also known as phenylmethyl silicone fluid, is a type of silicone oil. It belongs to the class of organosilicon compounds where the phenyl group (C₆H₅) is attached to the silicon atoms. These fluids are characterized by their high thermal stability, low surface tension, excellent lubricating properties, and resistance to oxidation and chemical breakdown. 

They find applications in various industries including cosmetics, pharmaceuticals, textiles, and as release agents and lubricants in mechanical and electrical applications.