mutation vs puddling

mutation

noun
  • A group of thrushes. 

  • An alteration a particular sound of a word, especially the initial consonant, which is triggered by the word's morphological or syntactic context and not by its phonological context. 

  • Any alteration or change. 

  • A mutant. 

  • Any heritable change of the base-pair sequence of genetic material. 

puddling

noun
  • A group of mallards (ducks). 

  • The act of lining a canal with puddle to make it watertight. 

  • The action of forming a puddle. 

  • The first true industrial process to produce steel from pig iron. 

  • A behaviour in which animals like butterflies seek out moist substances to obtain nutrients. 

  • The process of working clay, loam, pulverized ore, etc., with water, to render it compact, or impervious to liquids. 

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