Solar Plexus, what is the translation?

The “Solar Plexus” located above our navel, what is the english translation and why was it named that way. What is the reason that it is considered the center of our Body?
Regards

I found this definition for “solar plexus” AKA celiac (of the small intestine?) plexus: http://www.merriam-webster.com/dictionary/solar+plexus

I’m assuming you can say the whole “radiating” etymology can be likened to “solar” as in the literal radiation from the sun, and plexus, being a bundle of nerves…connecting to your small intestine?

Just a guess…nothing really concrete. After reading and researching your question, I suddenly feel a bit like doubling over and puking!

From the online etymology dictionary:

solar, c.1450, from L. solaris “of the sun,” from sol “sun” (see sol). Meaning “living room on an upper story” is from O.E., from L. solarium (see solarium). Solar power is attested from 1915. Solar system is attested from c.1704. Solar plexus (1771) “complex of nerves in the pit of the stomach,” apparently so called from its central position in the body.