What is the meaning of communications?

noun

• The activity of communicating; the activity of conveying information.
  • usage: "they could not act without official communication from Moscow"
  • synonyms: communication, communicating
• Something that is communicated by or to or between people or groups.
  • synonyms: communication
• A connection allowing access between persons or places.
  • usage: "how many lines of communication can there be among four people"; "a secret passageway provided communication between the two rooms"
  • synonyms: communication
• The discipline that studies the principles of transmiting information and the methods by which it is delivered (as print or radio or television etc.. )
  • usage: "communications is his major field of study"
  • synonyms: communication theory