The Flying Pussyfoot is the name of the train that the 1931 arc takes place in. It is a transcontinental train that was to be travelling from San Francisco to New York - until the Lemures take over, Ladd Russo 's team plans to take hostages and a group of delinquents abandon their attempts to make a train heist to save the passengers. While the Flying Pussyfoot and its passengers are all in commotion, there is also a mysterious beast called the Rail Tracer who kills people off one by one.
Flying is a slang term that could mean majestic or successful. Being a new transcontinental locomotive, this is fitting. Pussyfoot is another slang term that meant "to walk or go on carefully". Since the train was new, it is also fitting that the name is faring the passengers and crew well and telling them to have a safe trip.