protractor: meaning, definition, pronunciation and examples
B2Formal, Technical
Quick answer
What does “protractor” mean?
A flat, semi-circular or circular device, usually made of plastic or metal, used to measure or draw angles in degrees on paper.
Audio
Pronunciation
Definition
Meaning and Definition
A flat, semi-circular or circular device, usually made of plastic or metal, used to measure or draw angles in degrees on paper.
In anatomy, a muscle that causes a body part, like a limb or organ, to be drawn forward.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage for the primary sense. Spelling is identical.
Connotations
Universally associated with school geometry (maths/math) classes. Neutral connotations.
Frequency
Equally common in both varieties when referring to the geometry tool.
Grammar
How to Use “protractor” in a Sentence
use a protractor to [VERB]measure [NOUN] with a protractordraw [NOUN] using a protractorVocabulary
Collocations
Examples
Examples of “protractor” in a Sentence
verb
British English
- This tool is used to protract the line at a specific angle. (Rare, technical)
American English
- The surgeon will protract the limb during the procedure. (Rare, medical)
adjective
British English
- The protractor muscle is located in the shoulder. (Specialised)
American English
- He made a protractor measurement of the triangle's corners.
Usage
Meaning in Context
Business
Virtually never used.
Academic
Common in geometry, technical drawing, engineering, and architecture education.
Everyday
Primarily encountered in school contexts or when helping children with homework.
Technical
Precision instrument in drafting, design, and certain engineering calculations.
Vocabulary
Synonyms of “protractor”
Neutral
Weak
Vocabulary
Antonyms of “protractor”
Watch out
Common Mistakes When Using “protractor”
- Misspelling as 'protracter' or 'protraktor'.
- Using it to measure length instead of angles.
- Confusing it with a compass (for drawing circles).
FAQ
Frequently Asked Questions
Primarily yes, for measuring existing angles. Its secondary function is to draw (construct) angles of a specified size.
A protractor measures angles. A compass (drawing compass) draws circles and arcs, and can also be used to measure and transfer distances.
Yes, there are many digital protractor apps that use the device's sensors to measure angles in the real world, though they function differently from the traditional drawing tool.
Most angles measured in basic geometry are between 0 and 180 degrees. A semi-circle (180 degrees) is sufficient, cheaper to produce, and easier to handle and read than a full-circle version.
A flat, semi-circular or circular device, usually made of plastic or metal, used to measure or draw angles in degrees on paper.
Protractor is usually formal, technical in register.
Protractor: in British English it is pronounced /prəˈtræk.tər/, and in American English it is pronounced /proʊˈtræk.tɚ/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think: 'PRO' (professional) + 'TRACTOR' (like a tractor pulling something). A protractor 'pulls' or 'tracts' precise angles onto your page.
Conceptual Metaphor
A protractor is a MAP for angles; it charts the territory between two lines.
Practice
Quiz
In which of the following contexts is the word 'protractor' MOST likely to be used?