IPA: /ˌpriːhɪˈstɔːriən/
KK: /priˈhɪstəriən/
A person who studies or is an expert in the time before written history.
The prehistorian discovered ancient tools that provided insight into early human life.
Prehistorian → It is formed from "pre-" (meaning before) and "historian" (from Greek "histor" meaning one who knows or a learned person). The word refers to someone who studies the period before recorded history.
Think of someone who studies what happened 'before' ('pre-') history was recorded — that's what a prehistorian does.