A bollard. Spile is the word most frequently used on the Great Lakes to indicate a bollard
A term used in the Cornish tin mining industry referring to a metal bar or girder driven through broken rock to hold it in place while mining operations continue underneath the spiles. Typically a series of spiles are driven into the rock pile, and spiles are often used to close off a discontinued stope. The action of inserting spiles is referred to as "spiling" or "spiling-off"