Learn English – Antonym of coterminous, or single word for “having the same beginning”

single-word-requests

I find myself wanting to say that two things have their beginning together (not necessarily in time). The word coterminous came to mind, but that is the opposite of what I'm trying to say. I thought of simultaneous, but that is too punctiliar (whereas I want to express something more enduring, as implied by the word coterminous) and perhaps a little too time-laden.

So, for example:

To know the truth and to begin to know that you know the truth are <things-originating-inseparably>.

Is there a single English word for this?

Best Answer

coöriginal or cooriginal (not comparable)

(philosophy) Existing together ab initio; equiprimordial.  

(geometry, of a line) Originating from the same point in space.

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