What does the prefix meaga mean?

"Mega" is a prefix, not "meaga". It comes from the Greek word "megas," meaning "great" or "large."

In the context of measurement, "mega" signifies one million (1,000,000).

For example:

* Megaphone: A device that amplifies sound.

* Megaton: A unit of explosive power equivalent to one million tons of TNT.

* Megabytes (MB): A unit of computer data storage equal to one million bytes.