Definitions

1. noun

the outermost or final layer of something, especially a coat of paint or a protective covering

“The mechanic applied a topcoat of clear varnish to protect the car’s paint.”

2. noun

a heavy, long coat, typically worn on special occasions or in cold weather

“He put on his topcoat and gloves to brave the cold winter night.”

3. verb

to apply a final layer or coat to something, especially a surface

“The painter topcoated the wall with a glossy finish.”