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triangle
مثلث
triángulo
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triangle
त्रिभुज
triangolo
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三角形

das  Dreieck
A1
Estimated CEFR level.
/ˈdʁaɪˌɛk/

📐 What exactly is a Dreieck?

Das Dreieck primarily refers to a geometric figure defined by three points (Eckpunkte - corner points), which do not lie on a single straight line, and the straight lines (Seiten - sides) connecting them. The sum of the interior angles of a planar triangle is always 180 degrees.

There are different types of triangles, e.g.:

  • Gleichseitiges Dreieck: Equilateral triangle (all sides are equal length).
  • Gleichschenkliges Dreieck: Isosceles triangle (two sides are equal length).
  • Rechtwinkliges Dreieck: Right-angled triangle (one angle is 90 degrees).

Besides its geometric meaning, das Dreieck can also refer to:

  • 🎶 A musical instrument (a percussion instrument made of metal, also called Triangel in German).
  • 🔺 A warning symbol (e.g., das Warndreieck - warning triangle in traffic).
  • 💔 Figuratively, a relationship constellation involving three people (e.g., "Liebesdreieck" - love triangle).

⚠️ The word only takes the article das, regardless of the meaning.

🧐 Grammar Spotlight: Das Dreieck

The word "Dreieck" is a neuter noun (sächlich). It follows strong declension.

Singular Declension
CaseArticleNoun
NominativedasDreieck
GenitivedesDreieck(e)s
DativedemDreieck(e)
AccusativedasDreieck
Plural Declension
CaseArticleNoun
NominativedieDreiecke
GenitivederDreiecke
DativedenDreiecken
AccusativedieDreiecke

📝 Example Sentences

  1. Der Lehrer zeichnet ein Dreieck an die Tafel. (The teacher draws a triangle on the board.)
  2. Die Summe der Winkel eines Dreiecks beträgt 180 Grad. (The sum of the angles of a triangle is 180 degrees.)
  3. Im Orchester spielt jemand das Dreieck. (Someone in the orchestra plays the triangle.)
  4. Das Warndreieck ist ein wichtiges Sicherheitsinstrument im Auto. (The warning triangle is an important safety tool in the car.)
  5. Die Geschichte erzählt von einem komplizierten Liebesdreieck. (The story tells of a complicated love triangle.)

💡 How "das Dreieck" is used

Das Dreieck is very commonly used in mathematical and geometrical contexts. It's one of the most basic shapes.

  • Mathematics/Geometry: Calculation of areas, angles, side lengths (e.g., Pythagorean theorem in right-angled triangles - rechtwinklige Dreiecke).
  • Music: As the name for the percussion instrument triangle (also Triangel).
  • Road Safety: The Warndreieck (warning triangle) used to secure an accident site.
  • Figurative Meaning: Often in social contexts for constellations involving three parties, usually with a negative connotation (e.g., the "magic triangle" of economic policy - magisches Dreieck, love triangle - Liebesdreieck).

Comparison:

  • Viereck: A figure with four corners (quadrilateral).
  • Kreis: A round figure with no corners (circle).
  • Triangel: Often used synonymously for the musical instrument.

🧠 Mnemonics to Remember

For the article 'das': Think of 'das' geometric object or 'das' instrument. Many geometric shapes and abstract concepts in German are neuter (das Quadrat, das Rechteck, das Problem, das System). "Dreieck" fits this pattern: 'das' neutral, formal Dreieck.

For the meaning: The word itself helps! Drei (three) + Eck (corner/angle) = a figure with three corners. Quite logical!

🔄 Similar and Opposite Terms

Synonyms (similar meaning):

  • Triangel (mainly for the musical instrument)
  • (No direct synonyms for the geometric shape; descriptions like "dreiseitige Figur" - three-sided figure are possible)

Antonyms (opposite meaning):

  • For shapes: Viereck (quadrilateral), Fünfeck (pentagon), Kreis (circle) - (different number of corners or no corners)
  • (No direct antonyms in the figurative sense)

⚠️ Watch out for these!

  • Winkel: Means only the angle/corner itself, not the whole figure.
  • Spitze: Can be a corner/vertex of a triangle, but also refers to other pointed ends.

😂 A Little Joke

Warum ist das rechtwinklige Dreieck immer so entspannt?

Weil es immer einen rechten Winkel zum Chillen hat! 😎

---

Why is the right-angled triangle always so relaxed?

Because it always has a right angle (90 degrees) to chill at! 😎 (Pun: 'rechter Winkel' means right angle, but 'recht haben' can mean 'to be right' or imply having the right/privilege to do something, like chilling.)

📜 A Little Poem

Drei Ecken hat's, ganz klar und rein,
mal spitz, mal stumpf, mal grad und fein.
In Mathe hilft's, die Welt zu seh'n,
das Dreieck, wunderschön!Im Orchester klingt's hell und zart,
ein Schlag genügt, von eigner Art.

---

It has three corners, clear and pure,
Sometimes sharp, sometimes obtuse, sometimes straight and fine.
In math, it helps to see the world,
das Dreieck, beautiful!
In the orchestra, it sounds bright and delicate,
One strike is enough, of its own kind.

❓ Do you know the answer?

Ich habe drei Seiten, drei Ecken dazu,
find'st mich in der Mathe, im Nu.
Manchmal warne ich dich auf der Straß',
manchmal mach' ich Musik mit viel Spaß.

Was bin ich?

---

I have three sides, three corners too,
You'll find me in math, in a moment or two.
Sometimes I warn you on the street,
Sometimes I make music, oh what a treat.

What am I?

Solution: das Dreieck (the triangle)

🧩 More Tidbits

Word Composition: The word "Dreieck" is clearly composed of the number drei (three) and the noun das Eck (the corner/angle), plural: die Ecken.

Cultural References:

  • Bermudadreieck: Bermuda Triangle - An area in the Atlantic Ocean known for the supposed mysterious disappearances of ships and aircraft.
  • Goldenes Dreieck: Golden Triangle - A region in Southeast Asia known for opium cultivation.
  • Symbols: The triangle is used as a symbol in many cultures and contexts (e.g., the Trinity in Christianity, elements in alchemy).

📝 Summary: is it der, die or das Dreieck?

The word "Dreieck" is always neuter. The correct form is das Dreieck. The plural is die Dreiecke. It refers to a geometric shape, a musical instrument, or a relationship constellation.

🤖

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