What is "decamethylcyclopentasiloxane"

n. (context organic compound English) A particular cyclic siloxane.

Decamethylcyclopentasiloxane (D) is an organosilicon compound with the formula [(CH)SiO]. It is a colorless and odorless liquid that is slightly volatile. The compound is classified as a cyclomethicone. Such fluids are commonly used in cosmetics, such as deodorants, sunblocks, hair sprays and skin care products. It is becoming more common in hair conditioners, as it makes the hair easier to brush without breakage. It is also used as part of silicone based personal lubricants. D is considered an emollient. In Canada, among the volume used in consumer products approximately 70% were for antiperspirants and 20% for hair care products.