Symbol

noun

1. A character or glyph representing an idea, concept or object.

   "$ is the symbol for dollars in the US and some other countries."

2. A thing considered the embodiment of a concept or object.

   "The lion is the symbol of courage; the lamb is the symbol of meekness or patience."

3. A type of noun whereby the form refers to the same entity independently of the context; a symbol arbitrarily denotes a referent. See also icon and index.
4. A summary of a dogmatic statement of faith.

   "The Apostles, Nicene Creed and the confessional books of Protestantism, such as the Augsburg Confession of Lutheranism are considered symbols."

5. The numerical expression which defines a plane's position relative to the assumed axes.