straightedge
Học thuậtThân thiện
Definition
Noun: A straightedge is a hand tool with a perfectly straight edge, typically a flat, rigid bar made of metal, wood, or plastic. It is used for drawing straight lines or for checking if a surface or line is straight.
Usage
The word straightedge is used to refer to the physical tool itself. It is a countable noun. * A ruler can be used as a straightedge, but a straightedge itself often lacks measurement markings. * To draw a perfect line, align the straightedge with the two points and run your pencil along it. * Carpenters use a metal straightedge to check if a board is flat.
Examples
Advanced Usage
- As a modifier: The term can be used attributively (like an adjective) to describe other nouns.
- He made a straightedge cut using a guide and a circular saw.
- In Mathematics & Geometry: In formal geometric construction, a straightedge is an idealized tool used for drawing lines between points, but not for measuring distances. This is often paired with a compass.
Variants and Related Words
- Ruler: A measuring tool that also has a straight edge. All rulers can function as straightedges, but not all straightedges are rulers.
- Guide: A more general term for a tool or device that ensures straight or accurate motion (e.g., a saw guide).
- Level: A tool for checking horizontal or vertical alignment, which often incorporates a straight edge.
Synonyms
- Rule (when referring to its straight-edge function)
- Drawing guide
- Line guide
Related Phrases/Idioms
- Straightedge and compass: A standard phrase in classical geometry referring to the two basic tools allowed for geometric constructions.
- The problem of squaring the circle cannot be solved with only a straightedge and compass.
Noun
- hand tool consisting of a flat rigid rectangular bar (metal or wood) that can be used to draw straight lines (or test their straightness)