Meaning

noun a platform built out from the shore into the water and supported by piles; provides access to ships and boats

noun (architecture) a vertical supporting structure (as a portion of wall between two doors or windows)

noun a support for two adjacent bridge spans

originInherited from Middle English pere (“bridge pillar, breakwater”), from either Anglo-Norman pere (“stone”, from Latin petra) or Old French *piere (Old Northern French pire, from either Late Latin *petricus or pēra "satchel"); compare Medieval Latin pira.

Etymology from Wiktionary, CC BY-SA 3.0