adoptive mother vs mither

adoptive mother

noun
  • A woman who has adopted a child, as opposed to a biological mother. 

mither

noun
  • mother 

verb
  • To pester or irritate someone. 

  • To make an unnecessary fuss, moan, bother. 

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