dall

plural dalls

1. A tile with an incised surface.

   […] for such machine-made slate "dalls," or tiles, as perhaps we might call them, would soon be valued by the architect and builder for the roofs of many other classes of buildings as well as ecclesiastical ones.

   1872, Van Nostrand's Eclectic Engineering Magazine, page 646

   1 more example

   […] tiling. Thus arose those admirable roofs known in France as "en dallage," of which one most instructive example to both engineer and architect may be seen in those of the clerestory roofs of Nôtre Dame at Paris. The "dalls" being hand wrought[…]

   1872, The Engineer

1. A lake in Alaska.
2. The Dall River in British Columbia.
3. A surname. For example, William Healey Dall.