dead calm vs glassy

dead calm

adj
  • Completely still with no waves and no wind. 

noun
  • The condition of a perfectly flat sea with no waves and no wind. 

glassy

adj
  • Lacking any chop; smooth and mostly flat. 

  • Extensively glazed. 

  • Including a lot of glass. 

  • Dull; expressionless; lifeless. 

  • Of or like glass, especially in being smooth and somewhat reflective. 

noun
  • Glass marble. 

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