Before entering fully into the analysis of the meaning of the term meridian, it is advisable to proceed to determine its etymological origin. Thus, it must be made clear that it is a word that emanates from Latin, and more exactly from the word "meridianus". This is the result of the sum of two Latin words: "meridies", which can be translated as "noon" and which in turn is composed of "medius", which is synonymous with "medium", and "dies", which is equivalent a day".
Meridian It is a term that, according to the Royal Spanish Academy (RAE) , refers to belonging or relative to the time of noon . By extension, the concept is used as an adjective to name something that results very bright or very clear .
The meridians, on the other hand, are the maximum circles of the earth sphere that pass through the poles . It can be said that the meridians are imaginary lines , which are used to fix the schedule .
The base meridian from which lengths are measured is the Greenwich Meridian . This imaginary circumference that links the poles to the old astronomical observatory of the English city of Greenwich and was adopted as a reference in 1884 .
From north to south, the Greenwich Meridian go through United Kingdom , France , Spain , Algeria , Mali , Burkina Faso , Togo and Ghana .
It is interesting to note that currently one of the biggest tourist attractions of this English city is the Royal Astronomy Observatory, which dates from the second half of the 17th century. Thus, there are many visitors who dare to get to know it in depth and who are amazed by the exhibits that include both chronometers and all kinds of navigation tools. Of course, without forgetting that it has interesting watchmaking and observation of stars and planets.
The meridian that passes through the point where an observer is located is called local meridian . This meridian can be divided into two semi-circumferences by the axis of rotation of the land : he upper meridian (P.M ) and the lower meridian (A.M ).
He solar weather is the measure of weather which is based on the apparent movement of Sun over the horizon. When the sun passes through the meridian, it reaches its highest point in the sky and noon is set.
All this without forgetting that in the field of astronomy there is what is known as the meridian eyeglass, which is the one used to observe the stars and which is placed on a horizontal axis.
In addition to all of the above we would have to underline that there are other terms that also use the one that concerns us now. Thus, for example, is the so-called meridian plane, which is that plane that has the peculiarity of going through what would be the axis of revolution of a surface.
Other uses of the notion of meridian refer to the sofa without arms or backrest, the stretcher and the nap that is done after a meal.