A symbol that is universally recognized as a warning against substances that pose a threat to the health of living organisms, primarily that of humans.

A numero sign.

A lemniscate; the figure ∞ that represents infinity.

A circumscribed uppercase "A", denoting anarchy.

(chemistry) the 1- to 3-letter international code for a chemical element

plural of symbol group

(UK, retail) A form of retail franchise company that does not own or operate stores, but acts as a supplier to independent grocers, supermarkets, etc. which then trade under a common banner.

(literary) The leek as an emblem of Wales. / (geology) A specific symbol printed on geologic maps, Ꞓ, which denotes any Cambrian-age formation.

A language using symbols, such as hieroglyphs. / A form of shorthand in scientific or mathematic calculations.

(geometry) A notation that recursively encodes certain properties of a specified regular polytope or tessellation.