overburden

verb

1. (transitive)To overload or overtax.

   “In reality, the levels of work varied: some internationals seemed overburdened with tasks and responsibility, some seemed underburdened, and some faced apparently just the right amount of work.”

   “He said the increase would avoid overburdening taxpayers who have subsidised the railways by £31 billion since the start of the Coronavirus pandemic.”

noun

1. (countable, uncountable)The rock and subsoil that lies above a mineral deposit such as a coal seam, or any other underground feature.

   “Before much progress was made with the inverts, however, the movement became accelerated, and it was decided to lighten the load over the tunnel by removing some of the soil, […]. This reduction in the overburden arrested the movement, and the inverting and centring were completed, and the tunnel opened again to traffic on April 9, 1949.”

   “Such rocks have been changed by baking in a terrestrial pressure-cooker. Then they have been disinterred: kilometres of overburden must have been removed.”

   “Settari (2002) and Osorio et al. (1999) also suggest that the analysis domain should include overburdens, sideburdens and underburdens for better accommodation of the coupling effects of stress changes and flow.”

2. (countable, uncountable)A sterile stratum that lies above the stratum being investigated.