A snow was a two-masted sailing ship with rig very similar to that of a brig. It was used in coastal trading in Northern Europe during the eighteenth and nineteenth centuries.
The name refers to the “snow mast”, an auxiliary mast stepped just abaft (behind) the mizzen, or rearmost, mast holding the spanker or mizzen sail. This simplified sail handling; of some importance in commercial operations – certain fore-and-aft sail configurations also used the idea.