what is the difference between longitude and meridian
Senior Fellow in Electrical Engineering. The longitude of a point on earth is the angle, east or west, between that point. and a certain reference line on the earth. If you take a globe or a map and draw a line through all the points that have. exactly the same longitude, the line you get is the meridian of that longitude.The reference line is the meridian of zero longitude, called the Prime Meridian.atitude is the angle north or south between a place and the equator. Longitude is the angle east or west between the same place and the Prime Meridian. With only those two numbers, you can nail down any point on the Earth. 1 person found this useful.