The word 'snow' comes from 'snauw', which is an old Dutch word for beak, a reference to the characteristic sharp bow of the vessel.
The snow evolved from the (three-masted) ship: the mizzen mast of a ship was gradually moved closer towards the mainmast, until the mizzen mast was no longer a separate mast, but was instead made fast at the main mast top.
As such, in the 17th century the snow used to be sometimes classified as a three-masted vessel.

The snow dates back to the late 17th century and originally had a loose-footed gaff sail; the boom was introduced somewhere in the 18th century.
It was a popular type of vessel in the Baltic Sea and was employed by a large number of nations during its time.
The snow was considered a handy and fast sailing vessel, typically the largest two-masted vessel around, and was employed in both navy and merchant service.
When used as a military vessel, snows were, in the early 18th century, typically fitted with 5 to 16 guns.
Military snows were mostly used for coastal patrols and privateering, while in the merchant service, snows traded all the way to the Mediterranean and sometimes even sailed as far as the West Indies.

Snow: the largest of all old two-masted vessels.
The sails and rigging on the main mast of a snow are exactly similar to those on the same masts in a full-rigged ship; only that there is a small mast behind the mainmast of the former, which carries a sail nearly resembling the mizzen of a ship.

— Captain Charles Johnson, A General History of the Pyrates
The word 'snow' comes from 'snauw', which is an old Dutch word for beak, a reference to the characteristic sharp bow of the vessel. The snow evolved from the (three-masted) ship: the mizzen mast of a ship was gradually moved closer towards the mainmast, until the mizzen mast was no longer a separate mast, but was instead made fast at the main mast top. As such, in the 17th century the snow used to be sometimes classified as a three-masted vessel.
The snow dates back to the late 17th century and originally had a loose-footed gaff sail; the boom was introduced somewhere in the 18th century. It was a popular type of vessel in the Baltic Sea and was employed by a large number of nations during its time. The snow was considered a handy and fast sailing vessel, typically the largest two-masted vessel around, and was employed in both navy and merchant service. When used as a military vessel, snows were, in the early 18th century, typically fitted with 5 to 16 guns. Military snows were mostly used for coastal patrols and privateering, while in the merchant service, snows traded all the way to the Mediterranean and sometimes even sailed as far as the West Indies.
Snow: the largest of all old two-masted vessels. The sails and rigging on the main mast of a snow are exactly similar to those on the same masts in a full-rigged ship; only that there is a small mast behind the mainmast of the former, which carries a sail nearly resembling the mizzen of a ship.
— Captain Charles Johnson, A General History of the Pyrates
Snow (ship)