What is the meaning of the word "c clef"?

Definitions:

  1. A type of musical clef that indicated the position of middle C on the staff (the five lines on which music is written). copy to clipboard NOUN
    • The note on the first line of the alto clef is C. copy to clipboard
  2. Is a musical symbol placed at the beginning of a staff (the five lines on which music is written). copy to clipboard NOUN
    • The C-clef is never used on music written for the piano. copy to clipboard