Penannular means in the form of an incomplete circle or ring and may refer to:

Penannular brooch or Celtic brooch, a type of brooch clothes fasteners, often rather large Pseudo-penannular brooch, a related type that appears to be penannular, with two large terminals, but actually forms a complete circle Penannular ring Penannular bracelet A common form of earthworks; including some ditches around bowl barrows