Greatcoat (noun)

1. A long, thick overcoat worn in cold weather.
2. A heavy coat worn by soldiers or sailors.

Origin:

Great + coat, from the former large size of the coat, used to wear over armor.

Examples:

1. I put on my greatcoat before going out into the cold.
2. The soldier put on his greatcoat as the temperature dropped.
3. Greatcoats are typically made of wool or other warm materials.
4. Greatcoat is a heavy, long-sleeved overcoat worn in cold weather, especially by soldiers and sailors.
5. Greatcoat is a term used for a long, thick, overcoat worn in cold weather, typically made of wool or other warm materials.