an amount of time

of or relating to times before written history

(archeology) a period between the Stone and Iron Ages, characterized by the manufacture and use of bronze tools and weapons

(archeology) the period following the Bronze Age; characterized by rapid spread of iron tools and weapons

(archeology) the earliest known period of human culture, characterized by the use of stone implements

any period of time during which glaciers covered a large part of the earth's surface

belonging to or existing in times before recorded history

of or relating to times before written history

an archaeological period characterized by the use of copper for weapons and tools.

(archeology) a period between the Stone and Iron Ages, characterized by the manufacture and use of bronze tools and weapons

(archeology) the period following the Bronze Age; characterized by rapid spread of iron tools and weapons

(archeology) the earliest known period of human culture, characterized by the use of stone implements

any period of time during which glaciers covered a large part of the earth's surface