ETYM Old Eng. slabbe, of uncertain origin; perhaps originally meaning, a smooth piece, and akin to slape, Icel. sleipr slippery, and Eng. slip, v. i.
Thick piece of something.

ETYM Old Eng. tile, tigel, as. tigel, tigol, from Latin tegula, from tegere to cover. Related to Thatch, Tegular.
1. A flat thin rectangular slab (as of fired clay or rubber or linoleum) used to cover surfaces of buildings.
2. A thin flat slab of fired clay used for roofing; SYN. roofing tile.