from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A chart showing the horizontal variation in the magnetic force acting on a ship's compass needle by the iron within the ship, as a function of course steered
from The Century Dictionary and Cyclopedia
- n. A diagram containing a curve generated by the motion of a line drawn from a fixed origin, and representing in direction and magnitude the horizontal component of the force of magnetism on a ship's compass-needle while the ship makes a complete circuit.
- n. A diagram that shows both the horizontal directive magnetic force of the compass-needle on board ship under local influences and its deviation from the meridian for any latitude and sailing-course; specifically, the dygogram of Captain Colongue (1870) and of A. Smith, from which Paugger obtained the idea of his mechanical dromoscope of 1872.
From dynamic + goniometric + diagram (Wiktionary)