fricative vs sibilant

fricative

noun
  • Any of several sounds produced by air flowing through a constriction in the oral cavity and typically producing a sibilant, hissing, or buzzing quality; a fricative consonant. 

adj
  • produced by air flowing through a restriction in the oral cavity. 

sibilant

noun
  • A consonant having a hissing or hushing sound such as the s or sh in sack or shack. 

adj
  • Characterized by a hissing or hushing sound such as the s or sh in sack or shack. 

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