The snake in heraldry is a layered symbol of wisdom, renewal and guarded power. Because it sheds its skin, it naturally signifies rebirth, healing and the ability to begin anew, while its stealth and readiness to strike lend it connotations of vigilance, prudence and latent danger. Families that adopt a snake often wish to project careful counsel, an aptitude for strategy, or a lineage that has survived and adapted through testing times. At the same time the creature may evoke hidden knowledge, the safeguarding of secrets, or a stern moral caution about the perils that accompany ambition.

Heraldic associations are wide ranging. The snake is a common emblem of medicine and healing where it appears in the association of the Rod of Asclepius and on the arms of medical colleges and hospitals. It is also famously present in dynastic and civic contexts, most notably in the Milanese Visconti "biscione," a serpent devouring a human that became a powerful sign of territorial rule and identity. In municipal arms the device can indicate a local totem, an age-old legend, or a family name used in canting heraldry. Military or mercantile bearings sometimes use the snake to imply tactical shrewdness rather than brute force.

How the snake is drawn changes its message. A snake nowed or knotted suggests controlled strength or a binding oath, while a serpent biting its tail as an ouroboros speaks to eternity and continuity. A crowned serpent elevates the motif toward sovereignty or protected authority, and tincture choices shift nuance: gold for honourable guardianship, argent for purity of purpose, and sable for secrecy or mourning. For images and further reading consult the Wikimedia Commons collection of snakes in heraldry (Snakes in heraldry), The Heraldry Society (The Heraldry Society), Heraldry of the World (Heraldry of the World), the College of Arms (College of Arms), and Mistholme’s pictorial dictionary (Mistholme).