The Egyptian ankh also known as an ansate cross.
ankh definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a cross with a top loop, an ancient Egyptian symbol of life
Origin: Egyptian life, soul
ankh definition by American Heritage Dictionary
A cross shaped like a T with a loop at the top, especially as used in ancient Egypt as a symbol of life. Also called ansate cross.
Origin: Egyptian ‘nḫ, life.