overdraft UK /ˈəʊvədɹɑːft/US /ˈoʊvɚdɹæft/noun 5verb 1forms 3 noun5 •The act of overdrawing a bank account. •The extraction of groundwater from an aquifer beyond the safe yield or equilibrium yield. •The amount overdrawn.I have an overdraft of £1234. •The maximum amount that may be overdrawn.The bank have given me an overdraft of $2000. •A series of flues in a furnace; the current of air forced through them. verb1 •To extract groundwater from (an aquifer) beyond the safe yield or equilibrium yield. formsoverdrafted · overdrafting · overdrafts