primaeval

/praɪˈmivəl/
adjective
  1. Relating to the earliest times in the history of the world; very ancient.
    • In the primaeval ocean, the first simple life forms began to appear.
    • Scientists discovered primaeval fossils that are over 500 million years old.
    • The primaeval forest was so dense that sunlight barely reached the ground.
  2. Existing from the beginning; original or primitive in nature.
    • There is a primaeval fear of the dark that many people share.
    • The tribe still follows primaeval customs passed down for thousands of years.
    • The artist tried to capture the primaeval beauty of the untouched landscape.
Antonyms