Wire/ˈwaɪər/ Definition 1 of 4Pro Tip 1/3Material Matters The metal type can change wire's use and connotation. Guitar strings are often made of steel wire for durability. Pro Tip 2/3Physical Flexibility Wire is bendable, which makes it useful for various applications. You can shape a wire into a hook to hang your keys. Pro Tip 3/3Hidden Setup Wires are often concealed inside devices or walls. The electrician routed the wires behind the drywall.