<p><strong>Noun</strong></p><ul><li>rapidity in moving, going, traveling, proceeding, or performing; swiftness; celerity.</li><li>the speed of sound.</li><li>the speed of light.</li><li>the speed of sound.</li><li>relative rapidity in moving, going, etc.; rate of motion or progress.</li><li>full speed ahead.</li><li>full, maximum, or optimum rate of motion.</li><li>Automotive: a transmission gear ratio.</li><li>Photography: the sensitivity of a film or paper to light, measured by an ASA or DIN index.</li><li>Also called shutter speed: the length of time a shutter is opened to expose the film or digital sensor to light.</li><li>the largest opening at which a lens can be used.</li><li>Slang: a stimulating drug, as caffeine, ephedrine, or especially methamphetamine or amphetamine.</li><li>Informal: a person or thing that is compatible with or typical of one's ability, personality, desires, etc.</li><li>Archaic: success or prosperity.</li></ul><p><strong>Verb</strong></p><ul><li>to promote the success of (an affair, undertaking, etc.); further, forward, or expedite.</li><li>to direct (the steps, course, way, etc.) with speed.</li><li>to increase the rate of speed of (usually followed by up): to speed up industrial production.</li><li>to bring to a particular speed, as a machine.</li><li>to cause to move, go, or proceed with speed.</li><li>to expedite the going of: to speed the parting guest.</li><li>Archaic: to cause to succeed or prosper.</li><li>to move, go, pass, or proceed with speed or rapidity.</li><li>to drive a vehicle at a rate that exceeds the legally established maximum.</li><li>to increase the rate of speed or progress (usually followed by up).</li><li>to get on or fare in a specified or particular manner.</li><li>Archaic: to succeed or prosper.</li></ul>