apportion vs assign

apportion

verb
  • Specifically, to do so in a fair and equitable manner; to allocate proportionally. 

  • To divide and distribute portions of a whole. 

assign

verb
  • To transfer (property, a legal right, etc.) from one person to another. 

  • To give (a value) to a variable. 

  • To allot or give (something) as a task. 

  • To designate or set apart (something) for some purpose. 

  • To attribute or sort (something) into categories. 

  • To categorize (someone) as belonging to the male or female sex. 

  • To appoint or select (someone) for some office. 

noun
  • An assignee. 

How often have the words apportion and assign occurred in a corpus of books? (source: Google Ngram Viewer )