primordial (adj) – first, earliest or original; existing at or from the beginning of time; fundamental
BREAKDOWN: PRIM- (first) + ORD- (order) + -IAL (pertaining to)
This word is built on the root PRIM-, which means first, chief, or foremost.
Common PRIM- words include primary, primarily, primate, prime, and primitive.
More esoteric PRIM- words include primatology, primigenial, and primiparous.