Pentagon
UK[ˈpentəɡən]US[ˈpentəɡɑːn]
n
A flat shape with five straight sides and five angles.
n
(often the Pentagon) The building in Arlington, Virginia, that is the headquarters of the US Department of Defense, used as a symbol of the US military leadership.
Morpheme Breakdown
penta
gon
penta
five
gon
angle
Etymology
The word 'pentagon' is a direct borrowing from Late Latin pentagōnum, which itself originates from Greek pentagōnon, a noun use of the neuter form of pentagōnos meaning "five-angled". The Greek term is a compound of pente (five) and gōnia (angle). This logical, descriptive construction for a geometric shape entered English in the 16th century via Middle French. The modern application to the US military headquarters (capitalized as the Pentagon) is a metonymy, where the distinctive five-sided shape of the building comes to represent the institution it houses.
Analysis
Structure: penta (five) + gon (angle)
- penta: From Greek pente, meaning "five". It functions as a numerical prefix.
- gon: From Greek gōnia, meaning "angle" or "corner". It functions as a combining form denoting a figure with a specified number of angles.
Examples
A regular pentagon has five equal sides and five equal angles.
The policy decision was announced by officials at the Pentagon this afternoon.
Children were learning to draw different polygons, including a pentagon and a hexagon.