What does a bird witrh a circle around its head upside down in a triangle mean?

This strongly represents the Holy Spirit and the Holy Christian Trinity. The circle around the birds head is indicative of a halo, which represents the glory of God. The triangle represents the Christian Trinity (God the Father, God the Son (Jesus Christ of Nazareth and God the Holy Spirit Matthew 3: 16-17 says: "16As soon as Jesus was baptized, he went up out of the water. At that moment heaven was opened, and he saw the Spirit of God descending like a dove and lighting on him. 17And a voice from heaven said, "This is my Son, whom I love; with him I am well pleased." Hopes this helps answer your question.