pier 
(pîr)
(pîr)n.
1.
a. A platform extending from a shore over water and supported by piles or pillars, used to secure, protect, and provide access to ships or boats.
b. Such a structure used predominantly for entertainment.
2. A supporting structure at the junction of connecting spans of a bridge.
3. Architecture Any of various vertical supporting structures, especially:
a. A pillar, generally rectangular in cross section, supporting an arch or roof.
b. The portion of a wall between windows, doors, or other openings.
c. A reinforcing structure that projects from a wall; a buttress.
[Middle English per, bridge support, partly from Norman French pere, piere (from Old French puiere, a support, from puie, from puier, to support, from Vulgar Latin *podiāre, from Latin podium, platform; see PODIUM) and partly from Medieval Latin pera (from Old North French pire, piere, breakwater, possibly from Latin petra, rock, from Greek petrā; see per-2 in the Appendix of Indo-European roots).]