Rhumb line

Image of a loxodrome, or rhumb line, spiraling towards the North Pole

In navigation, a rhumb line, rhumb (/rʌm/), or loxodrome is an arc crossing all meridians of longitude at the same angle, that is, a path with constant azimuth (bearing as measured relative to true north). Navigation on a fixed course (i.e., steering the vessel to follow a constant cardinal direction) would result in a rhumb-line track.