Well, what do we call it?
The books I've been reading recently favour "Source". I'm not thrilled by the word. For one thing its homophone means something you put on your dinner and for another it lacks any of the resonance that comes from long use. But, again, that could be its strength. The traditional alternative is a funny, abrupt, little word that rhymes with "cod" and "sod" and has suffered so much mis-use it's now almost inseparable from the image of an ageing phallocrat dispensing judgement with his iron rod (another rhyme word- and one that keeps on forcing itself- in lieu of reputable alternatives- on hymn writers and Christian poets.)
So "Source" it may have to be. At least it doesn't have a bearded face. And the mental image that comes with it- of crystal waters "welling up unto eternal life" is attractive. Perhaps if I use it enough I'll find it begins to flow...