noun
pentadecagon
pen-tuh-DEK-uh-gon
Pentadecagon (noun) means a shape with fifteen straight sides and fifteen angles. Example: “The architect sketched a pentadecagon for the base of the pavilion.”
noun
1
technical A shape with fifteen straight sides and fifteen angles.
"The architect sketched a pentadecagon for the base of the pavilion."
"A regular pentadecagon has fifteen equal sides and fifteen equal angles."
"Drawing a pentadecagon by hand is far trickier than drawing a hexagon."
How to use pentadecagon
Learner’s notesIn plain EnglishA pentadecagon is simply a fifteen-sided shape.
When to use it
It is a specialist geometry term rather than everyday vocabulary.
Memory tip
Break the word into penta- (five) plus deca- (ten) to remember it means a fifteen-sided figure.
Trace the full origin ↓
Easily confused with
Common pairings
a regular pentadecagon
draw a pentadecagon
the sides of a pentadecagon
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The architect sketched a _____ for the base of the pavilion.
Etymology
The word joins the prefix pentadeca-, meaning fifteen, to the suffix -gon, meaning angle or corner, the same ending found in words like hexagon and octagon.
Synonyms
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15-gon
quindecagon
Rhymes for pentadecagon
See all rhymes for pentadecagon →Frequently asked questions
What is a pentadecagon?
It is a polygon with fifteen sides, so it also has fifteen interior angles.
Is pentadecagon the same as quindecagon?
Yes, quindecagon and 15-gon are alternative names for the same fifteen-sided shape.
Where does the word pentadecagon come from?
It comes from the Greek-derived elements pentadeca- (fifteen) and -gon (angle), the standard pattern used for naming polygons.
What is the meaning of pentadecagon?
"pentadecagon" (noun) means a shape with fifteen straight sides and fifteen angles.
