primeval
[adjective]
Synonyms: earliest, ancient, early, first, old, prehistoric, primal, primitive, primordial

[TahlilGaran] English Synonym Dictionary ▲

pri‧me‧val (also primaeval British English) /praɪˈmiːvəl/ adjective
[Date: 1600-1700; Language: Latin; Origin: primaevus, from primus ( ⇒ prime¹) + aevum 'age']

1. belonging to the earliest time in the existence of the universe or the Earth:
Primeval clouds of gas formed themselves into stars.

2. very ancient:
primeval forests

3. primeval feelings are very strong and seem to come from a part of people’s character that is ancient and animal-like:
the primeval urge to reproduce

[TahlilGaran] Dictionary of Contemporary English ▲