1. an arbitrary sign (written or printed) that has acquired a conventional significance
2. something visible that by association or convention represents something else that is invisible
the eagle is a symbol of the United States
3. A visible sign or representation of an idea; anything which suggests an idea or quality, or another thing, as by resemblance or by convention; an emblem; a representation; a type; a figure; as, the lion is the symbol of courage; the lamb is the symbol of meekness or patience.