The name has nothing to do with the vegetable "pea". A pea coating is the term used to refer to the overcoating worn by men. It traces its origins to the overcoat worn by sailors from the European and American fleets.
What is a pea coat?
The pea coating is a top coat usually made of heavy wool. The fabric used to make the fabric was called P-fabric for "pilot" and the jacket made from it became known as the P-jacket. They are characterized by the front overlapping wide collars, large fasteners and vertical cut pockets. They were designed to protect the sailors from the elements.
Deck hand to debonair
The rugged, woolly navy jacket worn by the sailors including the deck hands has now found favor among designers and fashionistas. The unchanged design of the pea coating has functionality and durability while being aesthetic. It is a medium-length cloak and covers the back while providing easy mobility. It is a tight fitting sheath with broad shoulders and narrow waist (reportedly worn even unbuttoned) and is characterized by a double-breasted lapel with two overlapping layers that help retain heat and prevent heat loss due to the cold winds. Another classic feature is its reverse capable convertible to protect against cold winds. It is adorned with large brass or wooden buttons that give it a distinct look. It's versatile enough to wear over a suit, or jeans and chunky boots, and sees the dashing debonair.