concern vs relaxation

concern

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

  • 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. 

relaxation

noun
  • Remission of attention or application. 

  • The transition of a nucleus, atom or molecule from a higher energy level to a lower one; the opposite of excitation 

  • The release following musical tension. 

  • A diminution of tone, tension, or firmness; specifically in pathology: a looseness; a diminution of the natural and healthy tone of parts. 

  • The act of relaxing or the state of being relaxed; the opposite of stress or tension; the aim of recreation and leisure activities. 

  • Unbending; recreation; a state or occupation intended to give mental or bodily relief after effort. 

  • Remission or abatement of rigor. 

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