noun

• A metal.
• A silvery-colored, toxic, metallic chemical element, liquid at room temperature, with atomic number 80 and symbol Hg.
• (sciences, historical) One of the elemental principles formerly thought to be present in all metals.
• (with definite article) Ambient pressure or temperature (from the use of mercury in barometers and thermometers).
• (obsolete) Liveliness, volatility.
• Any of several types of plant.
• An annual plant, annual mercury (Mercurialis annua), formerly grown for its medicinal properties; French mercury, herb mercury.
• Any plant of any species of the genus and the genus Mercurialis.
• A similar edible plant (Blitum bonus-henricus), otherwise known as English mercury or allgood.
• (US, regional) The poison oak or poison ivy.
• (astronomy) The planet in the solar system with the closest orbit to the Sun, named after the god; represented by ☿.
• (Roman mythology) The Roman god associated with speed, sometimes used as a messenger, wearing winged sandals; the Roman counterpart of the Greek god Hermes.
• (obsolete, alchemy, chemistry) Quicksilver, mercury. (No longer capitalized, as the name of the metal is no longer recognized as that of the planet.)
• (archaic) A carrier of tidings.
• A newsboy, a messenger.
• A footman.
• Someone who carries messages between lovers; a go-between.
• A newspaper.