A friend once said, "The reason why communication doesn't flow is that we worry more about what to say next than understanding what the other party is saying". For communication to flow, there must be feedback from an understood message. It's possible that two persons can talk without communicating because the core of communication is not in the number of words spoken but the depth to which the context of a message was transferred. Every communication requires a medium of transmission depending on the recipient of that message, the deaf can not be communicated through audio messages but with signs, and symbols, and other visual means.
Commune means "to be together or absorb" while "-ication" means a process. To sum it in my philosophy "commune -ication means the process of absorbing ideas, utilizing them and making decisions from the explicit knowledge ".
Communication requires feedback that could be in words or action. "Go get me the ball" is a message that requires an action to verify if the receiver understood the message. A signboard that has an arrow indicating a direction requires the other party to take an action, while verbal feedback is expected if a group of people converses over ideas and a debate topic.
Sometimes a message could communicate different meanings to different people. The same friend of mine once told me "If I keep buying things I don't want, very soon I will start selling things I need", as straightforward as the statement was, I did not understand it until I had a personal experience, then it occurred to me what that statement meant. This implies that not all communication is understood at that moment, sometimes it demands a personal experience to absorb a message.
There are various means of communication, verbal and nonverbal and individuals also have channels for understanding communication better; either through audio, video, signs, symbols, etc. Until a channel best understood by an individual is used, the communication may not flow.