Stoker
A stoker is the crewman on a ship or train who is responsible for maintaining the furnace room, getting his name from his responsibility to tend the flame. "The Stoker" is the title of the short story that Kafka expanded into the story Amerika.
Der Verschollene
This German phrase translates to "The Lost," or "The Missing" and is often employed in conversations about Amerika because it was the German project name for the novel.
Theatre company
The falling action of the plot involves Brußmann being hired to be a technical worker for a theatre company, which basically means that he will travel with the traveling performers helping as a stage hand. Theatre companies used to be a major source of entertainment back before television and film brought entertainment to culture in more universe ways.