triangle - Master This Word
Master this word with our 5-step learning method – Learn English in English
triangle Word Meanings
- A three-sided polygon.
- A shape formed by connecting three points.
- The figure associated with the triangle inequality.
triangle Example Sentences
Example sentences are the start of understanding. Don't rush to memorize. First feel how the word works in a sentence.
triangle Phonetic & Pronunciation
UK
/ˈtraɪ.æŋ.ɡəl/
US
/ˈtraɪ.æŋ.ɡəl/
triangle Word Etymology
tri- = three, angle = corner; Latin → Old French → English. Imagine a figure skater making a triangular shape on the ice, perfectly balancing between the three points.
Note 1: These definitions and etymologies are not standard dictionary definitions, but extended explanations provided to help with memorization and understanding of the actual application of words. Through this background information, we strive to make words more vivid and easier to understand, and help you remember their meanings in real life.
Note 2: LexiTalk designs the learning flow around the linguistics principle of “Comprehensible Input.” When learners encounter material that is slightly above their level but still understandable from context, the brain naturally absorbs the language. That’s why we keep every word inside authentic contexts, using examples and associations to help you understand it and use it flexibly.
Read the FAQ explanation of Comprehensible InputReal Context
Triangles are among the simplest polygons and appear in many everyday contexts, from road signs to art and architecture. In geometry, a triangle is defined by three edges and three vertices, but there are many different types based on side length or angle: equilateral, isosceles, and scalene; acute, right, and obtuse. The word triangle comes from Latin tri- meaning three and angulus meaning angle, reflecting its origin through Old French into English. Imagine a figure skater making a triangular shape on the ice, balancing between three points.
Usage Reminders
- Note the three main classifications: by sides (equilateral, isosceles, scalene) and by angles (acute, right, obtuse). Count three sides when identifying a triangle. The sum of interior angles is always 180 degrees. Use the term triangle rather than 'triangulo' when speaking English. Remember the etymology tri- + angle for memory. Practice with simple sketches to fix the concept.
Common Misconceptions
- A triangle has four sides.
- Any three lines that form a loop must be a triangle.
- All triangles are right triangles.
- A triangle can have curved edges.
- Three points always make a triangle.
Thinking Differences
Learners often picture triangles as simply any three lines forming a loop, which can lead to confusion about sides and angles. English emphasizes the shape and its properties (three sides, angle sum 180).
Learning Tips
- Draw triangles to practice three sides and three vertices.
- Label sides as a, b, c and angles as A, B, C.
- Memorize the three side-types: equilateral, isosceles, scalene.
- Memorize the three angle-types: acute, right, obtuse.
- Use the terms triangle inequality and triangle sum in contexts.
- Compare with other polygons to see what makes a triangle unique.
5-Step Learning Method - Learn English in English
Step 1: Meaning
What is the meaning of the word 'triangle'?
A.A three-sided polygon
B.A square shape
C.A circular figure
D.A five-pointed star
Step 2: Usage
Which of the following is a correct usage of the word 'triangle'?
A.I ate a delicious triangle.
B.He carries a triangle in his pocket.
C.The cat chased the triangle.
D.She drew a triangle on the paper.
Step 3: Similar Words
What is a synonym for the word 'triangle'?
A.Rectangle
B.Circle
C.Trigon
D.Square
Step 4: Opposite Words
What is an opposite (antonym) for the word 'triangle'?
A.Circle
B.Square
C.Line
D.Hexagon
Step 5: Mastery
In what real-life context would you commonly see a triangle?
A.In a music concert
B.In a cooking show
C.In a geometry class
D.In a sports event
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