income vs salary

income

noun
  • Money one earns by working or by capitalising on the work of others. 

  • A disease or ailment without known or apparent cause, as distinguished from one induced by accident or contagion; an oncome. 

  • That which is taken into the body as food; the ingesta; sometimes restricted to the nutritive, or digestible, portion of the food. 

  • Money coming in to a fund, account, or policy. 

salary

noun
  • A fixed amount of money paid to a worker, usually calculated on a monthly or annual basis, not hourly, as wages. Implies a degree of professionalism and/or autonomy. 

verb
  • To pay on the basis of a period of a week or longer, especially to convert from another form of compensation. 

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