Capable of being allotted; able to be distributed or assigned as a portion or share.
From allot plus -able suffix (capable of being). The root comes from Old French 'aloter' and the original meaning of assigning shares. This is a standard adjective formation in English.
In agriculture and urban planning, 'allottable land' refers to property that can be legally divided and distributed to people—it's a legal designation that comes from the same concept as allotment gardens where cities give citizens small plots to farm.
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