a cappella vs twiddle

a cappella

noun
  • A vocal performance with no instrumental accompaniment. 

adv
  • In a manner of a choir with no instrumental accompaniment; literally, "in the style of the (Sistine) Chapel (in Rome)", such as a musical Mass done a cappella. 

adj
  • Singing solely or mainly without instrumental accompaniment. 

  • Related to a form of purely vocal music mostly associated with American college performance groups. 

twiddle

noun
  • A small musical flourish. 

  • A small decorative embellishment. 

  • A slight twist with the fingers. 

  • A wiggling movement. 

  • A tilde. 

  • A tiny bit 

  • A drawn line that is curvy or twisted. 

  • A tizzy 

verb
  • To flip or switch two adjacent bits (binary digits). 

  • To play with anything; hence, to be busy about trifles. 

  • To wiggle, fidget or play with; to move around. 

  • To be in an equivalence relation with. 

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