First Known Use: 1570
Dictionary
pentagon
noun pen·ta·gon \ˈpen-tə-ˌgän\
mathematics : a flat shape that has five sides and five corners
the Pentagon : the building in Washington, D.C., that is the headquarters of the U.S. Department of Defense
: the leaders of the U.S. military
Full Definition of PENTAGON
: a polygon of five angles and five sides
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Origin of PENTAGON
Greek pentagōnon, from neuter of pentagōnos pentagonal, from penta- + gōnia angle — more at -gon
Rhymes with PENTAGON
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Pentagon
noun
Definition of PENTAGON
: the United States military leadership
Origin of PENTAGON
the Pentagon building, headquarters of the Department of Defense
First Known Use: 1945
PENTAGON Defined for Kids
pentagon
noun pen·ta·gon \ˈpen-tə-ˌgän\
Definition of PENTAGON for Kids
: a flat geometric figure having five angles and five sides
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