guttate vs occasional

guttate

adj
  • Shaped like, or resembling drops. 

  • Spotted. 

verb
  • To exude drops of xylem sap on the edges of leaves. 

occasional

adj
  • Occurring or appearing irregularly from time to time, but not often. 

  • Created for a specific occasion. 

  • Acting in the indicated role from time to time. 

  • Intended for use as the occasion requires. 

noun
  • A person who does something only occasionally. 

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