ark
n. countablen. a large boat or ship, especially one built to save people or animals from a disaster. It often refers to the famous wooden ship from the Bible story of Noah.
n. a large, capacious vessel or ship, specifically the one built by Noah for the preservation of life during the Deluge. Often used figuratively to describe a place of protection or a vessel containing a significant collection of items.
The story says Noah built a giant ark to survive the flood.
In the movie, the scientists built a modern ark to save humanity from the rising sea levels.
The seed vault in the Arctic serves as a botanical ark, preserving the genetic diversity of the world's crops against the threat of global catastrophe or extinction.
When referring to the biblical vessel or the Ark of the Covenant, it is almost always capitalized.