We've been talking today below the equator about spurs and rowels. In taking a closer look at spurs through MW online, I found this term that is interesting regarding boats and spurs:

Main Entry: spur shore Pronunciation Guide
Function: noun
: a timber or spar designed to hold a boat away from a pier wharf or quay

A spur on a rider is shaped somewhat like a wishbone on a turkey. I wonder about this timeber that holds the boat away. Is it on the wharf or on the boat, I wonder?