Mom and Pop vs firm

Mom and Pop

firm

noun
  • A criminal gang, especially based around football hooliganism. 

  • A business partnership; the name under which it trades. 

  • A business enterprise, however organized. 

adj
  • Durable, rigid (material state) 

  • Fixed (in opinion). 

  • Insistent upon something, not accepting dissent. 

  • Steadfast, secure, solid (in position) 

verb
  • To become firm; stabilise. 

  • To make firm or strong; fix securely. 

  • To improve after decline. 

  • To make compact or resistant to pressure; solidify. 

  • To shorten (of betting odds). 

  • To select (a higher education institution) as one's preferred choice, so as to enrol automatically if one's grades match the conditional offer. 

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