An effective date or as of date is the date upon which something is considered to take effect. This may be different from the date upon which the event actually occurs or is recorded.
Famous quotes containing the words effective and/or date:
“The atomic bomb certainly is the most powerful of all weapons, but it is conclusively powerful and effective only in the hands of the nation which controls the sky.”
—Lyndon Baines Johnson (1908–1973)
“In the South, the war is what A.D. is elsewhere: they date from it.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)