What does "pentagon" mean?
A polygon with five sides and five angles.
Pentagon
/ˈpɛn.təˌɡɑn/ name, noun
name, noun ·Uncommon ·Advanced level
Meaning at a glance
- Primary sense: A polygon with five sides and five angles.
- Grammar: pentagon is listed as name, noun.
- Nearest alternatives: 5-gon, figure, fin, five-gon.
- Useful contrasts: circle, quad, quadrangles.
- Usage evidence: Pentagon officials won't say when the problem turned up and refused to discuss details about the flight.
How to use "pentagon"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "pentagon" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "pentagon" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "pentagon" as the right word for your sentence.
If your draft is formal, technical, persuasive, or sensitive, compare "pentagon" with a nearby alternative so the final choice matches both meaning and reader expectation.
Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "pentagon" is acting as name, noun in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "5-gon" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.
Final meaning check
Before publishing a sentence with "pentagon", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 A polygon with five sides and five angles.
"Imagine a vast sheet of paper on which straight Lines, Triangles, Squares, Pentagons, Hexagons, and other figures, instead of remaining fixed in their places, move freely about, […]"
- 2 the United States military establishment wordnet
- 3 A fort with five bastions.
- 4 a five-sided polygon wordnet
Proper Noun
- 1 The headquarters of the United States Department of Defense.
- 2 The United States Department of Defense. metonymically
"The Vietnamese people inspired youth of all nationalities […] by demonstrating that the determination of a people to fight for their sovereignty and right to self-determination was an unconquerable force, even in the face of Pentagon might."
Synonyms
All synonymsAntonyms
Example
"Pentagon officials won't say when the problem turned up and refused to discuss details about the flight."
Common questions
What is a synonym for "pentagon"?
Common synonyms include: 5-gon, figure, fin, five-gon, five-sided polygon, pentagon headquarters.
How do you use "pentagon" in a sentence?
Pentagon officials won't say when the problem turned up and refused to discuss details about the flight.
How do you pronounce "pentagon"?
Pronounced /ˈpɛn.təˌɡɑn/.
Etymology
Etymology 1
From Middle French pentagone, from Late Latin pentagōnum, from Ancient Greek πεντάγωνον (pentágōnon), noun use of the neuter of the adjective πεντάγωνος (pentágōnos, “five-angled”), from πέντε (pénte, “five”) + -γωνος (-gōnos, “angled”). Equivalent to penta- + -gon.
Etymology 2
From the shape of the building.