Allotment

Allotments in the travel industry refer to blocks of travel inventory (such as hotel rooms or airplane seats) that are bought out in bulk by a bed bank, tour operator, airline consolidator, DMC, or other wholesaler. 

Typically, allotments are purchased for a season (e.g., beach or ski season) or specific dates (e.g., around holidays or special local events) and then resold to travel retailers or directly to end customers.

Allotment sales help suppliers reduce the risk of unsold inventory, while resellers benefit from discounted prices, earning on a margin.

An allotment in a broad sense is a share or part of something given to someone.