ceiling zero vs foggy

ceiling zero

foggy

adj
  • Being, covered with, or pertaining to fog (“tall grass etc that grows after, or is left after, cutting; moss”) 

  • Obscured by mist or fog; unclear; hazy 

  • Confused, befuddled, etc. 

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