at ease vs mistrustful

at ease

prep
  • Allowed to refrain from being in rigid formation. 

  • Free of anxiety; not stressed or tense. 

  • In a relaxed position with the feet apart rather than at attention. 

mistrustful

adj
  • Having a suspicion, imagining or supposing (that something undesirable is the case). 

  • Expressing or showing a lack of trust. 

  • Having mistrust, lacking trust (in someone or something). 

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