Crossword Genius

Vast timespan (3)

Ross

I believe the answer is:

eon

(Other definitions for eon that I've seen before include "thousand million years" , "Huge time period" , "Immense period" , "Very long age" , "Vast age; eternity" .)

I've seen this clue in the Penny Press.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.