Committed cost is sunk cost which has been already incurred in past and which has to be incurred by entity for future obligations. This cost is not relevant for any decision making in short run.
Committed cost is also know as sunk cost, it is cost which has already been incurred in the past. It is not relevant for decision making and is caused by complete abandonment as against temporary shut down. This should be constrasted with discretionary costs, which are avoidable costs.