From Zenith To Nadir

I Can Tell What You're Thinking -
Not through trickery, since DARPA have now been reunited with their long-borrowed Telepathy Helmet in almost full working order, or so I hear.
     No, I can tell you expect this Intro to go on about that 2000AD character "Zenith", who was a repellent little goitre pursuing a career as a manufactured pop-star.  Art?

Thus

     Oh, and he was super-powered, too, though it took considerable prodding for him to do anything heroic, as he was initially as yellow as his trousers above.
     As for "Nadir", well, naturally you were expecting me to be going on about that stalwart champion of the consumer, good ol' Ralph.  Art?

Close enough

     Wrong on both counts!
     I think we can ignore Zenith, as that's what would annoy him the most, and instead concentrate on "Nadir", which came up as the answer in one of my crosswords.
     What is it?  Conrad wasn't too sure himself, except that he thinks it refers to the lowest point of anything, so what does the Collins Concise define it as?
     "The point on the celestial sphere directly below an observer and diametrically opposite the zenith".  Art?

The celestial sphere.
(Well, it's not a golf-ball, is it?)

     Where is this word derived from?  O I thought you'd never ask!  From the Arabic, actually, and the phrase "Nazir as-samt", which means "beneath the zenith".
     HOORAY YET ANOTHER WORD NOT DERIVED FROM GREEK OR LATIN!
     OUCH THAT COINCIDENCE HYDRA'S GOT IT'S TEETH IN MY BEHIND AGAIN

Really!  Where are your manners?

     For this is the third word in three days that we have found with no derivation back to that zombie language Latin, and the inescapable, unavoidable Greek.  That makes my fusion-powered pumping unit work at 5% over capacity.
     Ooops.  That was only supposed to be a couple of lines about "Nadir".  Okay, consider it your factoid of the day, motley, and then we can go back to toasting giant crumpets with a blowtorch.

Made up of yum

     Blimey, I shall have to call it a night, I keep falling asleep in my chair and drooling on the keyboard.  Old age catching up with Your Humble Squire, methinks, as a whole bottle of Bombay Sapphire can't possibly have anything to do with it.