adjunctive vs helping verb

adjunctive

noun
  • a substance added as a supplement; often in the phrase "additives and adjunctives." 

  • a connector joining two components of the same weight, such as a coordinating conjunction 

adj
  • forming an adjunct 

  • additional; neither basic nor primary 

  • the property of two operations x and y, such that ax(ayb) = a, and ay(axb) = a 

helping verb

noun
  • An auxiliary verb; a verb that accompanies the main verb in a clause. 

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