primal in WordNet English dictionary

1. having existed from the beginning; in an earliest or original stage or state
   "aboriginal forests"; "primal eras before the appearance of life on earth"; "the forest primeval"; "primordial matter"; "primordial forms of life"
   aboriginal  primal  primeval  primaeval  primordial 
   
2. serving as an essential component
   "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
   cardinal  central  fundamental  key  primal