cowardly vs quaking

cowardly

adj
  • Showing cowardice; lacking in courage; weakly fearful. 

quaking

adj
  • Shaking uncontrollably, especially due to fear or awe; trembling or shivering. 

noun
  • The action of the verb quake. 

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