Prehistoric (8)
'prehistoric' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ancient that I've seen before include "Old salt in Coleridge's poem" , "Antediluvian" , "Very old, like the poetic mariner" , "Historic standard" , "Antiquated" .)
'prehistoric' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for primeval that I've seen before include "From the earliest times" , "having come first in history" , "Ancient" , "Very old" , "Belonging to the Earth's beginnings" .)