Castellanus

Clouds that present, in at least some portion of their upper part, cumuliform protuberances in the form of turrets or towers (crenellated), some of which are taller than they are wide, and are connected by a common base and seem to be arranged in lines. The castellanus character is especially evident when the clouds are seen from the side.

This term applies to Cirrus, Cirrocumulus, Altocumulus and Stratocumulus.