TASK DEFINITION: You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.
PROBLEM: Category: THE CIVIL WAR 
Clue: A century before the U.S.S. Nautilus, the Confederacy had 2 of these new ships, the Pioneer  & the Hunley

SOLUTION: submarines

PROBLEM: Category: POTPOURRI 
Clue: Goto is the surname of the young Osaka-born violinist known by this single name

SOLUTION: midori

PROBLEM: Category: FOREIGN WORDS & PHRASES 
Clue: The name of this heavy blade is Spanish, probably from a word meaning "a large hammer"

SOLUTION:
a machete