patchy vs vacillant

patchy

adj
  • Not constant or continuous; intermittent or uneven. 

  • Full of, or covered with, patches; abounding in patches. 

vacillant

adj
  • Vacillating; wavering; fluctuating; irresolute. 

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