North

North is a cardinal direction, one of the four main compass points. It lies directly opposite south and forms a right angle with both east and west. The word can function as a noun, adjective, or adverb when describing orientation or location.

Etymology

The term "north" shares roots with the Old High German nord, both tracing back to the Proto-Indo-European ner-, meaning "left" or "below." This association comes from the fact that north is to the left when one faces the rising sun, a pattern linking all cardinal directions to the sun's position. In Latin, borealis derives from the Greek boreas, the north wind personified as the god Boreas, father of Calais and Zetes. Another Latin term, septentrionalis, comes from septentriones ("seven plow oxen"), a name for the Ursa Major constellation.

The Greek arktikós, also named for that constellation, gives English the word "Arctic." Other languages have unique derivations: in Lezgian, kefer means both "disbelief" and "north," referencing non-Muslim peoples historically living north of the Lezgian homeland. In many Mesoamerican languages, north also means "up." The old Romanian word for north is mĭazănoapte, from Latin mediam noctem ("midnight"), while Hungarian észak comes from éjszaka ("night"), because between the Tropic of Cancer and the Arctic Circle the sun never shines from the north. North is often abbreviated as N.

Mapping and navigation

By convention, the top of a map points north. To navigate north with a compass, one sets a bearing or azimuth of 0° or 360°. Traveling directly north follows a meridian line upward. In Western culture, north is considered the fundamental direction: it defines all other directions, and the top edges of maps usually correspond to the northern edge of the area shown, unless landmarks or explicit notes indicate otherwise.

On any rotating astronomical object, north typically denotes the side that appears to rotate counterclockwise when viewed from afar along the axis of rotation. However, the International Astronomical Union defines the geographic north pole of a planet or satellite as the pole in the same celestial hemisphere, relative to the Solar System's invariable plane, as Earth's north pole. This means some objects, like Uranus, rotate retrograde—clockwise when seen from the IAU north.

Magnetic north and declination

Magnetic north is the direction a properly functioning magnetic compass points. The difference between magnetic north and true north is called magnetic declination. For many purposes, ignoring this difference is acceptable; in other cases, compensation based on known declination solves the problem.

Simple generalizations on this topic are often unsound and may reflect popular misconceptions about terrestrial magnetism. Maps for orienteering clearly indicate local declination for easy correction. Maps may also show grid north, the direction northward along the grid lines of a map projection.

Roles of north as prime direction

The visible rotation of the night sky around the celestial pole provides a strong metaphor for north as "up" in the Northern Hemisphere, though the Southern Hemisphere lacks a prominent visible analog to the Pole Star. Chinese and Islamic cultures traditionally considered south as the proper top of maps. In Polynesian cultures, winds—prevailing or ancestral—often defined cardinal points. In Western culture, maps are usually drawn with true or magnetic north at the top.

Globes place the North Pole at the top, or in the top half if the axis is inclined. Maps typically label which direction corresponds to a real-world direction, often with a single arrow for true north, occasionally for magnetic north, or two arrows for both. A compass rose may appear, but usually on maps with north at the top and with north decorated more prominently.

The notion that north should always be "up" and east at the right was established by the Greek astronomer Ptolemy. Historian Daniel Boorstin suggested this may be because most known places in his world were in the northern hemisphere, making them most convenient for study in the upper right corner of a flat map. North is often associated with colder climates, as most of the world's populated high-latitude land lies in the Northern Hemisphere. The Arctic Circle passes through the Arctic Ocean, Norway, Sweden, Finland, Russia, the United States (Alaska), Canada (Yukon, Northwest Territories, and Nunavut), Denmark (Greenland), and Iceland.