A fixed allotment is a predetermined amount of something that is allocated to a specific person or group. In this case, the crossword solutions for the term 'fixed allotment' are 'RATION' and 'QUOTA'. A RATION is an amount of something, usually food, that is given to someone as part of their daily allowance. A QUOTA is a predetermined amount of something that is assigned to a particular person or group. Both terms refer to a fixed allotment, which is an amount of something that is allocated to a specific person or group.