Demurrage

n. delay; payment for delay

Demurrage from demur, French demeurer, to delay, derived from Latin, mora) is a general term used to indicate a surcharge for delays in delivering a product. It has application in a variety of fields. In industries where items are sold in rented containers, demurrage is synonymous with the free rental of the container for a given period of time. The assumption is that a given amount of free time using the container is built into the cost of the item.
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Noun
1. a charge required as compensation for the delay of a ship or freight car or other cargo beyond its scheduled time of departure
(hypernym) charge
2. detention of a ship or freight car or other cargo beyond its scheduled time of departure
(hypernym) delay, holdup

(n.)
The detention of a vessel by the freighter beyond the time allowed in her charter party for loading, unloading, or sailing.
  

(n.)
The allowance made to the master or owner of the ship for such delay or detention.
  

excess time taken for loading or unloading a vessel/container thus causing delay of scheduled departure. Shipper pays compensation.