slackness vs tenseness

slackness

noun
  • A subgenre of dancehall music with sexual lyrics. 

  • The state of being slack; the quality of having slack. 

  • Vulgarity in West Indian culture. 

tenseness

noun
  • A particular vowel or consonant quality that is phonemically contrastive in many languages, including English. 

  • The characteristic of being tense. 

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