Spats, a shortening of spatterdashes, or spatter guards are a type of footwear accessory for outdoor wear, covering the instep and the ankle. Spats are distinct from gaiters, which are garments worn over the lower trouser leg as well as the shoe.
Woolen spats
Claude Rains wearing spats in 1912
U.S. Navy Ceremonial Guard wear white canvas leggings as part of their Enlisted Full Dress Whites.
Gaiters are garments worn over the shoe and bottom of the pant or trouser leg and used primarily as personal protective equipment, in particular against snakebite; similar garments used primarily for display are spats.
Hiking gaiters
U.S. Navy Ceremonial Guard wearing white canvas leggings, as the part of the Enlisted Full Dress Whites or Blue
Over-the-knee gaiters worn by a Chilean rodeo rider
The Bishop of Lichfield, in Vanity Fair, 1897