underburden verb 2noun 1forms 3 verb2 •To give too light a burden; to assign less than a fair share.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. — 2007 •To assign less work than someone or something is capable of.After five days of unsatisfactory work, we came to the conclusion that the furnace was underburdened. — 1909 noun1 •The rock and subsoil that lies below a mineral deposit such as a coal seam.Much of the heat introduced with the steam is lost to the overburden and to the underburden by thermal conduction in the manner discussed earlier. — 1991 formsunderburdened · underburdening · underburdens