The unicorn is among the most admired creatures in heraldry, combining beauty, strength, and moral purity in a single emblem. Traditionally shown as a horse-like beast with a single spiralled horn, cloven hooves, a goat’s beard, and often a lion’s tail, it represents chastity, virtue, courage, healing, and untamed power. Medieval belief held that the unicorn could only be captured by a maiden, which gave it strong associations with innocence, truth, and spiritual grace. At the same time, its horn was thought to detect or neutralize poison, making it a fitting symbol of protection and incorruptibility. Heraldic descriptions and forms are discussed in Parker’s Glossary of Heraldry and Mistholme’s Heraldry Dictionary.

In coats of arms, the unicorn may appear as a charge, crest, badge, or supporter. It is often shown rampant, collared, chained, or armed and crined in a contrasting colour. The chain is especially significant in British heraldry: it suggests that a fierce and noble force has been mastered and placed in the service of lawful authority. Religious and moral meanings are common, especially in medieval and Renaissance contexts, where the unicorn could symbolize Christ, purity, sacrifice, or the triumph of virtue over corruption. In family heraldry, it can also indicate high ideals, independence, courage, and a reputation for honour.

The most famous heraldic example is the unicorn supporter of the Royal Arms of Scotland, later paired with the English lion in the royal arms of the United Kingdom, where it represents Scotland’s proud and independent heraldic tradition. Unicorns also appear in the arms of noble families, civic bodies, and institutions throughout Europe, with many examples catalogued by Heraldry of the World. Because it unites purity with ferocity, the unicorn remains one of heraldry’s most compelling symbols of noble virtue, guarded sovereignty, and spiritual strength.