ノア Noa = Noah — named for Noah's Ark of Genesis, the colossal vessel that preserves life through a world-ending flood. Apt for a half-island-sized ark the Fish-Man Island ancients built during the Void Century and bound to a centuries-old promise (its in-story epithet is the 'Ship of Promise,' 約束の舟 Yakusoku no Fune). The biblical-salvation register name-encodes its later reveal as a vessel of deliverance tied to Joy Boy.
A colossal structure in the deep-sea Fish-Man District · the New Fish-Man Pirates’ base · first appeared @0608
Profile
Noah — a colossal dark structure in the deep-sea Fish-Man District of Fish-Man Island, serving as the New Fish-Man Pirates’ base and the seat of their (still-shadowed) boss (Ch. 608 pp. 8, 17). Only its shadowed interior is shown this chapter; its full form and scale are not yet depicted, though its size and the biblical-ark name register as significant.
On-page events
Fish-Man Island — Noah’s true purpose disclosed (Ch. 649)
King Neptune reveals (pp. 17-18) that Noah was meant to be used by Joy Boy and moved by the Neptunians, was taken to the Forest of the Sea after the Void Century ended, and is protected by the Ryugu royal line through the generations until “the day the promise comes about,” when “Noah will fulfill its actual purpose.” Binds Noah to Joy Boy, the Poneglyph apology, and the Poseidon power. See Noah Awaits Its True Purpose When The Promise Is Fulfilled.
Fish-Man Island — purpose revealed (partial) (Ch. 648)
Fish-Man Island — “the ship of promise” stopped by the Sea Kings (Ch. 647)
Fish-Man Island — weaponized over Conchcorde Plaza (Ch. 644)
Fish-Man Island — Noah falls toward the island (Ch. 643)
Fish-Man Island — moved against the island; the decoy run (Ch. 642)
Fish-Man Island — the falling ark + its true purpose (Ch. 641)
Fish-Man Island — full reveal + the fall (Ch. 640)
Fish-Man Island — the New Fish-Man Pirates’ deep-sea base (Ch. 608) — first appearance
Fish-Man Island — the hull over the district (Ch. 611)
Fish-Man Island — the villain alliance beneath Noah (Ch. 613)
Fish-Man Island — Decken rages aboard Noah (Ch. 631)
Fish-Man Island — Noah revealed as a movable ancient ark, hurled at Shirahoshi (Ch. 632)
Fish-Man Island — “the ark of prophecy” begins to move (Ch. 636)
Fish-Man Island — “The Ancient Ark” weaponized and falling (Ch. 637)
Fish-Man Island — the ark as homing weapon, chasing the princess (Ch. 638)
Etymology
Confidence: high · ノア Noa = “Noah.” Named for Noah’s Ark (Genesis 6–9) — the giant vessel that preserves life through a divine flood. The choice is load-bearing rather than decorative: Noah is a half-island-sized ark built by Fish-Man Island’s ancients during the Void Century and kept against a centuries-old promise, its in-story epithet the “Ship of Promise” (約束の舟 Yakusoku no Fune, @0636). The biblical register — a great ship of salvation awaiting a covenant’s fulfillment — name-encodes the arc’s later reveal of Noah as a Joy-Boy-linked vessel of deliverance the Sea Kings are sworn to pull (see Noah The Giant Ark In The Deep Sea). Source: One Piece Wiki — Noah.