Slate is a type of rock or a flat piece of this rock used for roofing and stuff.
1.\ta fine-grained rock formed by the metamorphosis of clay, shale, etc., that tends to split along parallel cleavage planes, usually at an angle to the planes of stratification.
2.\ta thin piece or plate of this rock or a similar material, used esp. for roofing or as a writing surface.
3.\ta dull, dark bluish gray.
4.\ta list of candidates, officers, etc., to be considered for nomination,...