concern vs lookout

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. 

lookout

noun
  • A subject for observation; a prospect or view. 

  • A session of watching for an approaching enemy, police, etc. 

  • A person on watch for approaching enemy, police, danger, etc. 

  • A vantage point with a view of the surrounding area. 

  • A joist that extends in cantilever out from the exterior wall (or wall plate) of a building, supporting the roof sheathing and providing a nailing surface for the fascia boards. 

  • An observation window. 

  • One's perspective, outlook; hence, one's responsibility. (used with a possessive pronoun or a noun in a possessive form). 

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