Penannular Brooch

Penannular means “almost closed”. Penannular brooches are of ring form which are not fully closed and with a pin sometimes fitting in the opening. Many Celtic cloak pins are of this design.
Celtic Penannular Brooches, c.7th-8th Century. © The Trustees of the British Museum.

Celtic Penannular Brooches, c.7th-8th Century.
© The Trustees of the British Museum.