The symbol for actinium on the table of elements is an example of Ac.
The listing in the index of a Bible for the Acts section is an example of Ac.
An example of AC is what runs in a home to keep it cool in the summer.
The label on an appliance that can run on an alternating current is an example of AC.
A date that is from before the era of Christ is an example of AC.
Origin of ac
- Fr -aque < L -acus < Gr -akos (or directly < any of these)
From Webster's New World College Dictionary, 5th Edition
- New Latin -acus from Greek -akos
From American Heritage Dictionary of the English Language, 5th Edition