shaky vs solid as a rock

shaky

adj
  • Easily shaken; tottering; unsound. 

  • Shaking or trembling. 

  • Wavering; undecided. 

  • Full of shakes or cracks; cracked. 

  • Nervous, anxious. 

solid as a rock

adj
  • Extremely thick and heavy, so as to make it impossible to move. 

  • Very reliable and dependable 

How often have the words shaky and solid as a rock occurred in a corpus of books? (source: Google Ngram Viewer )