Wikipedia nonsense - meridian and metre

1)

Meridian (geography) - Wikipedia, the free encyclopedia
en.wikipedia.org/wiki/Meridian_(geography)‎
Wikipedia
A meridian (or line of longitude) is the half of 
an imaginary great circle on the Earth's surface

2)

History of the metre - Wikipedia, the free encyclopedia
en.wikipedia.org/wiki/History_of_the_metre‎
Wikipedia
1⁄10,000,000 part of the quarter of a meridian

From 2:

1 m = 1⁄10,000,000 of the quarter of a meridian

Insert 1:

1 m = 1⁄10,000,000 of the quarter of a (half of 
an imaginary great circle on the Earth's surface)

Reduce

1 m = 1⁄10,000,000 of 1/4 of 1/2 of imaginary great circle on the Earth's surface
1 m = 1/80,000,000 of imaginary great circle on the Earth's surface

Reformulate

imaginary great circle on the Earth's surface = 80,000,000 m = 80,000 km