What is the meaning of Dead_weight?

Unremitting heavy weight that does not move.

The largest weight of cargo a ship is able to carry; i.e, the weight of a ship when fully loaded minus its weight when empty.

Dead load.

That which is useless or excess; that which slows something down.

The total (unpowered) weight of a train to be propelled (or hauled) by the locomotive; another locomotive being hauled dead as part of the train is a dead weight.

With just enough weight for a ball to drop into a pocket, or come to rest in a precisely determined position.

Source: wiktionary.org