lagging

Insulation used to prevent heat diffusion, as from a steam pipe.

A wooden frame built especially to support the sides of an arch until the keystone is positioned.

The act of walking or moving slowly, or of falling behind.

In architecture, the planking, consisting of narrow strips, extending from one rib of the centering of an arch, vault, or tunnel to another, and affording direct support to the voussoirs until the arch or vault is closed in.

In mining, strips of wood or light timbers laid across the stulls in the drifts to prevent fragments of rock from falling through.