nonpositive vs second string

nonpositive

adj

  • Not positive. 

  • Not positive; either zero or negative. 

noun

  • Any value that is not positive. 

second string

adj

  • Not as good; of a lower quality or condition. 

noun

  • A unit of players which is considered to have a secondary level of talent and which usually plays after the first string. 

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