cribrum cri·brum (krī'brəm, krĭb'rəm)
n. pl. cri·bra (krī'brə, krĭb'rə)
A horizontal lamina that fits into the ethmoidal notch of the frontal bone and supports the olfactory lobes of the cerebrum. Also called cribriform plate of ethmoid bone.
His κόσκινον or sieve (cribrum Eratosthenis) was a device for discovering all prime numbers.