The chemical symbol for mercury is "Hg." This symbol comes from the Latin name "hydrargyrum," which means "water-silver" due to the element's silvery liquid form at room temperature. Mercury is a transition metal and is often found in nature in various mineral forms, but it is most commonly associated with the liquid state used historically in thermometers, barometers, and other scientific instruments. However, due to its toxic properties and environmental concerns, the use of mercury has been significantly restricted in many applications, prompting the search for safer alternatives.