The phrase "buy Dyson hair dryer" is a verb, referring to the act of purchasing a specific brand and type of hair dryer. A real-world example could be: "I need to buy a Dyson hair dryer because my current one is outdated."
Purchasing a Dyson hair dryer is relevant because it represents an investment in high-quality hair care. Its benefits include advanced technology for quick drying and damage prevention, as well as ergonomic design for comfort. Historically, the introduction of Dyson hair dryers marked a significant development in the hair care industry, revolutionizing the way people style their hair.