octagon

1 of 2

noun

oc·​ta·​gon ˈäk-tə-ˌgän 

: a polygon of eight angles and eight sides

octagonal

äk-ˈta-gə-nᵊl 

adjective

octagonally

äk-ˈta-gə-nᵊl-ē 

adverb

octagonal

2 of 2

adjective

oc·​tag·​o·​nal (ˈ)äk¦tagənᵊl 

-taig-

: having eight sides

built a mansion in the shape of an octagon, which started quite a fashion for octagonal houses

—Time

octagonally

-ᵊlē 

-ᵊli

adverb

Examples of octagon in a Sentence

Recent Examples on the Web

Noun

Hernandez is a grappler in the octagon who can unleash crushing blows with his fists, elbows and legs. — Joe Davidson, Sacbee.com, 21 Aug. 2026

Barboza, who hadn't secured a win since October 2023 and had taken significant damage in recent bouts, laid his gloves down in the octagon. — Brian Mazique, Forbes.com, 16 Aug. 2026

Goodall’s son, Simon, has also worked with the Ultimate Fighting Championship, dressing its octagons for events in Britain. — Chris McKenna, New York Times, 22 July 2026

Conor McGregor has finally revealed what exactly happened to his right knee during a very short return to the UFC octagon on July 11 in Las Vegas. — Scott Thompson, FOXNews.com, 20 July 2026

Word History

Etymology

Noun

Latin octagonum, from Greek oktagōnon, from okta- + -gōnon -gon

Adjective

alteration (influenced by octagon) of earlier octogonal, from Middle French, from octogone octagon (from Latin octagonum, octogonum) + -al

First Known Use

Noun

1594, in the meaning defined above

Rhymes for octagon

• aileron
• antiphon
• autobahn
• carillon
• castellan
• celadon
• cephalon
• cynodon
• denouement
• deuteron
• echelon
• epsilon

Kids Definition

octagon

noun

oc·​ta·​gon ˈäk-tə-ˌgän 

: a polygon with eight angles and eight sides

octagonal

äk-ˈtag-ən-ᵊl 

adjective