accession vs reduction

accession

noun
  • A coming to; the act of acceding and becoming joined. 

  • A mode of acquiring property, by which the owner of a corporeal substance which receives an addition by growth, or by labor, has a right to the part or thing added, or the improvement (provided the thing is not changed into a different species). 

  • The act of coming to or reaching a throne, an office, or dignity. 

  • The invasion, approach, or commencement of a disease; a fit or paroxysm. 

  • Access; admittance. 

  • A group of plants of the same species collected at a single location, often held in genebanks. 

  • Complicity, concurrence or assent in some action. 

  • Agreement. 

  • The act by which one power becomes party to engagements already in force between other powers. 

  • Increase by something added; that which is added; augmentation from without. 

verb
  • To make a record of (additions to a collection). 

reduction

noun
  • The act, process, or result of reducing. 

  • a transformation of one problem into another problem, such as mapping reduction or polynomial reduction. 

  • An arrangement for a far smaller number of parties, e.g. a keyboard solo based on a full opera. 

  • A reduced price of something by a fraction or decimal. 

  • The amount or rate by which something is reduced, e.g. in price. 

  • A reaction in which electrons are gained and valence is reduced; often by the removal of oxygen or the addition of hydrogen. 

  • The rewriting of an expression into a simpler form. 

  • The process of rapidly boiling a sauce to concentrate it. 

  • A philosophical procedure intended to reveal the objects of consciousness as pure phenomena. (See phenomenological reduction.) 

  • The ratio of a material's change in thickness compared to its thickness prior to forging and/or rolling. 

  • A medical procedure to restore a fracture or dislocation to the correct alignment, usually with a closed approach but sometimes with an open approach (surgery). 

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