Meaning

noun an indefinitely short time

noun a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel

noun a midwestern state in central United States; a border state during the American Civil War, Missouri was admitted to the Confederacy without actually seceding from the Union

originDisputed, with many speculative suggestions; see Wikipedia.

Etymology from Wiktionary, CC BY-SA 3.0