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deca·gon | \ ˈde-kə-ˌgän 
\
\Definition of decagon
: a plane polygon of 10 angles and 10 sides
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More Definitions for decagon
decagon
noundeca·gon | \ ˈde-kə-ˌgän \
\Kids Definition of decagon
: a closed figure having ten angles and ten sides
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Time Traveler for decagon
The first known use of decagon was circa 1639
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