lubber's point
Học thuậtThân thiện
Definition
Noun: A fixed reference line marked on a compass, specifically a ship's compass, that aligns with the ship's centerline (keel). It is used to read the ship's heading directly by seeing which compass degree the line points to.
Usage
The lubber's point is a critical navigational aid on a vessel. The helmsman or navigator aligns the ship's course so that the desired compass bearing is directly under or opposite this fixed line.
Examples
- The captain instructed the new sailor to steer the ship until the lubber's point aligned with 270 degrees, a westerly course.
- To check our heading, simply look at which degree marking on the compass card the lubber's point is indicating.
Advanced Usage
- "To steer by the lubber's point": This phrase describes the fundamental act of steering a ship by keeping the desired compass bearing aligned with this fixed line.
- In aviation, a similar fixed reference mark on an aircraft's compass is called a lubber line, serving the identical purpose of indicating the craft's heading.
Variants and Related Words
- Lubber line: The more common modern term, synonymous with "lubber's point." It is used in both maritime and aviation contexts.
- Lubber's mark: A less common variant with the same meaning.
Synonyms
- Heading indicator (in a broader, functional sense, though this is often a separate instrument).
- Reference line.
Notes
The term "lubber" is an old nautical word for an unskilled sailor or landsman. The "lubber's point" was a simple, foolproof reference designed for clarity. It is a fundamental component of a magnetic compass installation on any vessel.
Noun
- a fixed line on a ship's compass indicating its heading