lubber's mark
Học thuậtThân thiện
Definition
Noun: - A fixed reference line on a ship's compass, specifically the lubber's line, which is aligned with the ship's keel to indicate the vessel's heading relative to the compass card.
Usage
The term is used in nautical contexts to refer to the stationary mark or line on a compass against which the heading is read. It is the point of reference for the helmsman or navigator to determine the direction the ship is pointing.
Examples
- Noun:
- The helmsman kept the north point of the compass card aligned with the lubber's mark to maintain a steady course.
- Before setting sail, the captain checked that the lubber's mark was correctly positioned relative to the ship's bow.
Advanced Usage
- "to steer by the lubber's mark": To navigate by keeping the compass card aligned with this fixed reference line.
- In the thick fog, the sailor had to steer strictly by the lubber's mark.
Variants and Related Words
- Lubber's line: The more common and precise term for the same fixed reference line on a compass.
- The lubber's line must be installed parallel to the ship's centerline for accurate readings.
- Lubber line: A shortened, synonymous form.
Synonyms
- Heading indicator: A more general term for a device or mark showing direction.
- Reference line: A broad term for a fixed line used as a guide.
Notes on Meaning
This term is highly specialized and is only used in the context of marine navigation. It does not have other general meanings. The word "lubber" historically refers to an unskilled sailor, but in this compound term, it specifically denotes the fixed compass mark.
Noun
- a fixed line on a ship's compass indicating its heading