Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “octagon”

octagon

noun [C]     /ˈɒk.tə.ɡən/ US  /ˈɑːk.tə.ɡɑːn/
a flat shape with eight sidesGeometrical shapesSpherical, circular and annular objects octagonal     /ɒkˈtæɡ.ən.əl/ US  /ɑːk-/ adjective an octagonal (= with eight sides) towerGeometrical shapesSpherical, circular and annular objects
(Definition of octagon noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of octagon

Definitions of “octagon” in other dictionaries

Word of the Day

handout

a document given to students or reporters which contains information about a particular subject

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More