100-year flood (wun-HUN-drehd YEER FLUD)
noun.

flood that has a one-percent chance of occurring any year. 

13th Amendment thir-TEENTH uh-MEHND-mehnt
noun.

update to the U.S. Constitution making slavery illegal.

14th amendment (for-TEENTH uh-MEHND-mehnt)
noun.

update to the U.S. Constitution guaranteeing all citizens equal protection and due process under the law.

15th amendment (FIHF-teenth uh-MEHND-mehnt)
noun.

update to the U.S. Constitution that allows all citizens the right to vote.

1918 flu pandemic (NIN-teen AY-teen FLOO pan-DEHM-ihk)
noun.

(1917-1920) infectious disease that killed between 50 million and 100 million people worldwide, with healthy young adults being the most vulnerable. Also called the Spanish flu.

19th amendment (NIN-teenth uh-MEHND-mehnt)
noun.

update to the U.S. Constitution allowing women citizens the right to vote.

2004 Indian Ocean tsunami (2004 IHN-dee-un OH-shun SOO-nah-mee)
noun.

(December 26, 2004) violent earthquake and resulting tsunami that struck off the west coast of Sumatra, Indonesia.

2012 phenomenon (TWEHN-tee TWEHLV fuh-NAH-mih-nahn)
noun.

set of varied beliefs that predict a catastrophic event occuring on December 21, 2012.

3-D (THREE DEE)
adjective.

something appearing in three dimensions, giving the appearance of depth.

3-D map (THREE-DEE MAP)
noun.

representation of spatial information using dimensions of depth, length, and width.