What is this symbol (cross with P loop atop)? I have seen in a church a cross with a loop off the top that makes the vertical look like a P. Does this symbol have a name? What is its meaning? From what does it derive? Can you supply any more interesting information about it? The loop was to my right, and was more flag-like than a P, so drooping a bit.
Actually, this symbol is a "tau-rho," not a "chi-rho." Instead of being a shortened form of the word "Christ" (Χριστος), generally speaking the Tao-Rho is thought to be a shortened form of the words "cross" and "crucify" (σταυρος, σταυροω). Larry Hurtado has speculated that it may also be the first pictoral representation of Jesus on a cross (the loop of the "P" is the head). See Hurtado's The Earliest Christian Artifacts pp. 135ff, he calls it a "staurogram."