concern vs thought

concern

noun
  • A worry; a sense that something may be wrong; an identification of a possible problem. 

  • The placement of interest or worry on a subject. 

  • The expression of solicitude, anxiety, or compassion toward a thing or person. 

  • That which affects one’s welfare or happiness. A matter of interest to someone. 

  • A business, firm or enterprise; a company. 

  • Any set of information that affects the code of a computer program. 

verb
  • To engage by feeling or sentiment; to interest. 

  • To relate or belong to; to have reference to or connection with; to affect the interest of; to be of importance to. 

  • To make somebody worried. 

thought

noun
  • Anxiety, distress. 

  • A very small amount, distance, etc.; a whit or jot. 

  • A way of thinking (associated with a group, nation or region). 

  • The operation by which mental activity arise or are manipulated; the process of thinking; the agency by which thinking is accomplished. 

  • Representation created in the mind without the use of one's faculties of vision, sound, smell, touch, or taste; an instance of thinking. 

  • The careful consideration of multiple factors; deliberation. 

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