prehistoric

a prehistoric megalithic structure

They have found prehistoric remains.

prehistoric finds made in an unexplored cave

my dad's electric typewriter was a prehistoric machine.

Archaeologists attribute the ruin to a flourishing prehistoric kingdom.

The intact carcass of the prehistoric animal was prevented from putrefying by the arctic cold.

Local folklore has it that prehistoric men drove cattle over these cliffs.

that it has been populated from prehistoric times is evidenced by the remains of Neolithic buildings.

ponderous prehistoric beasts. Figuratively it describes what is complicated, involved, or lacking in grace:

With its leathery skin, long tail, short legs, and needle-like teeth, the Nothosaur resembled a prehistoric crocodile.