"A large nail or pin, generally of iron. The larger forms of spikes, particularly railroad spikes, are chisel-pointed, and have a head or fang projecting to one side to bite the rail. Spikes are also made split, barbed, grooved, and of other shapes." —Whitney, 1889
Illustration of a dock spike, used in building docks and piers.
William Dwight Whitney, PhD, LLD The Century Dictionary: An Encyclopedic Lexicon of the English Language (New York, NY: The Century Co., 1895) 5831