The Tyet, also known as the knot, buckle, or blood of Isis, is the symbol of the Egyptian goddess Isis. Tyet roughly translates as "well being" or "life". Its original symbolism is somewhat disputed, it has been said to represent everything from an actual buckle or sash used in securing clothing, to the female reproductive organs.
What ever it was originally intended to represent, it was a sacred talisman whose protection was believed to extend into the afterlife. As such it was often included in funeral amulets to protect the body of the deceased. This amulet was thought to be especially effective against thieves and poisonous insects and animals.