This stop sign is a hexagon.
The definition of a hexagon is a figure with six sides.
A stop sign with six sides is an example of a hexagon.
a plane figure with six angles and six sides
Origin of hexagonClassical Latin hexagonum ; from Classical Greek hexagōnon, hexagon, neuter of hexagōnos, six-cornered ; from hex, six + gōnia, a corner, angle: see knee
A polygon with six sides and six angles.
Origin of hexagonLatin hexagōnum, from Greek hexagōnos, having six angles : hexa-, hexa- + -gōnos, angled; see –gon.