Related Clues:

• History text topic
• It may have periods
• Feminist pitcher's concern?
• Geological time
• Geologist's time division
• Oft-nicknamed period
• Geological period
• Important time
• Strengthen, in a way
• Supply (with)
• End of an ___
• Piece of the past
• Memorable age
• Napoleonic, for one
• Prominent span of years