different between dividing vs apportionment

English

dividing (not comparable)

Serving to divide or separate.
We installed a dividing wall in order to create two rooms out of one.

dividing

present participle of divide
Dividing seven dollars among three people is difficult!

dividing (plural dividings)

An act of division.
- 1840, Albert Barnes, Notes: Critical, Explanatory, and Practical on the Book of the Prophet Isaiah
  Hence the noun also means dividing, or portion as that which is divided — whether an inheritance, or whether the dividings of spoil after battle.

apportion +? -ment

apportionment (plural apportionments)

The act of apportioning or the state of being apportioned.
- This new-comer was a man who in any company would have seemed striking. […] He was smooth-faced, and his fresh skin and well-developed figure bespoke the man in good physical condition through active exercise, yet well content with the world's apportionment.
(US) The distribution of members of the House of Representatives according to the population of the various states.
(US) The allocation of direct taxation according to the population of the various states.

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