"shirker," 1914, World War I armed forces slang, from earlier verb meaning "to swindle, cheat" (1902) from the old con game of selling spurious "gold" bricks (attested by 1882).
Slang definitions & phrases for goldbrick
goldbrick
noun
(also goldbricker) A shirker; a person who avoids work or duty; goof-off(WWI armed forces)