deading
Webster's Dictionary (GCIDE)
Lagging \Lag"ging\, n.
1.(Mach.) The clothing (esp., an outer, wooden covering), as of a steam cylinder, applied to prevent the radiation of heat; a covering of lags; -- called also deading and cleading. [1913 Webster]
2.Lags, collectively; narrow planks extending from one rib to another in the centering of arches. [1913 Webster]