argute vs sibilant

argute

adj

  • Shrill in sound. 

  • Sharp; perceptive; shrewd. 

sibilant

adj

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

noun

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

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