Altitude above the actual surface, either land or water, of a planet or natural satellite.

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1.On the beach, shore, or land (as opposed to aboard or on board). 2. Towards the shore. 3. 'To run ashore': To collide with the shore (as opposed to 'to run aground,' which is to strike a submerged feature such as a reef or sandbar)


A satellite based radionavigation system providing continuous worldwide coverage. It provides navigation, position, and timing information to air, marine, and land users.


A slender triangular recess cut into the faying surface of a frame or steamed timber to fit over the land of clinker planking, or cut into the faying edge of a plank or rebate to avoid feather ends on a strake of planking. The feather end is cut off to produce a nib. The joggle and nib in this case is made wide enough to allow a caulking iron to enter the seam.


  1. Moving away from the shore.
  2. Of a wind, blowing from the land to the sea.
  3. At some distance from the shore; located in the sea away from the coast.


  1. A stone or concrete structure on navigable water used for loading and unloading vessels, generally synonymous with a wharf, although the solid foundations of a quay contrast with the closely spaced piles of a wharf. When 'quay' and 'wharf' are used as synonyms, the term 'quay' is more common in everyday speech in the United Kingdom, many Commonwealth countries, and the Republic of Ireland, while 'wharf' is more commonly used in the United States.
  2. To land or tie up at a quay.


A ship used to carry soldiers. Troopships are not specially designed for military operations and unlike landing ships cannot land troops directly onto a shore; instead they unload troops at a harbor or onto smaller vessels for transportation to shore.


A correction due to nonstandard air temperature, particularly the sextant altitude correction due to changes in refraction caused by difference between the actual temperature and the standard temperature used in the computation of the refraction table. The Nautical Almanac refraction table is based upo


Angular distance above the horizon; the arc of a vertical circle between the horizon and a point on the celestial sphere, measured upward from the horizon. Angular distance below the horizon is called negative altitude or depression. Altitude indicated by a sextant is called sextant altitude. Sextant altitude corrected only for inaccuracies in the reading (instrument, index, and personal errors, as applicable) and inaccuracies in the reference level (principally dip) is called apparent or rectified altitude. After all corrections are applied, it is called corrected sextant altitude or observed altitude. An altitude taken directly from a table, before interpolation, is called tabulated altitude. After interpolation, or if determined by calculation, mechanical device, or graphics, it is called computed altitude. If the altitude of a celestial body is computed before observation, and sextant altitude corrections are applied with reversed sign, the result is called precomputed altitude. The difference between computed and observed altitudes (corrected sextant altitudes), or between precomputed and sextant altitudes, is called altitude intercept or altitude difference. An altitude deter- mined by inexact means, as by estimation or star finder, is called an approximate altitude. The altitude of a celestial body on the celes- tial meridian is called meridian altitude. The expression ex- meridian altitude is applied to the altitude of a celestial body near the celestial meridian, to which a correction is to be applied to deter- mine the meridian altitude. A parallel of altitude is a circle of the celestial sphere parallel to the horizon, connecting all points of equal altitude.


An azimuth determined by solution of the naviga- tional triangle with altitude, declination, and latitude given. A time azimuth is computed with meridian angle, declination, and latitude given. A time and altitude azimuth is computed with meridian angle, declination, and altitude given


An enclosed basin used to place a ship on dry land so that all the submerged parts and fittings can be repaired.

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