What is the meaning of indication?

noun

• Something that serves to indicate or suggest.
  • usage: "an indication of foul play"; "indications of strain"; "symptoms are the prime indicants of disease"
  • synonyms: indicant
• The act of indicating or pointing out by name.
  • synonyms: denotation
• Medicine) a reason to prescribe a drug or perform a procedure. (
  • usage: "the presence of bacterial infection was an indication for the use of antibiotics"
• Something (as a course of action) that is indicated as expedient or necessary.
  • usage: "there were indications that it was time to leave"
• A datum about some physical state that is presented to a user by a meter or similar instrument.
  • usage: "he could not believe the meter reading"; "the barometer gave clear indications of an approaching storm"
  • synonyms: reading, meter reading