滑石 is read as かっせき (kasseki) and means talc.
かっせき
kasseki
かっせきこ
talcum powder
なめらか
continuously differentiable
すべる
to fail (an examination)
こっけい
ridiculous
すべりだい
(playground) slide
かっそう
taxiing
かっそうろ
runway
かっこう
downhill (race)
ぬめり
slime
すべりだす
to make a start
すべりこむ
to slide into
かつらく
sliding down (a slope, mountainside)