n. 保热套

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}.

2. Lags, collectively; narrow planks extending from one rib
to another in the centering of arches.