Present participle of allot; the act of distributing or assigning shares or portions to people.
From allot plus -ing suffix (present participle). The root comes from Old French 'aloter' and the practice of assigning shares. This is a standard verbal form formation.
Every time a teacher is 'allotting' time for different lessons or a restaurant is 'allotting' tables to customers, they're participating in a tradition of fair distribution that goes back centuries to when 'lots' literally meant random fate assignments.
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