What is the meaning of minus?

noun

• An arithmetic operation in which the difference between two numbers is calculated.
  • usage: "the subtraction of three from four leaves one"; "four minus three equals one"
  • synonyms: subtraction

adjective

• On the negative side or lower end of a scale.
  • usage: "minus 5 degrees"; "a grade of B minus"
• Involving disadvantage or harm.
  • usage: "minus (or negative) factors"
  • synonyms: negative