is a specific kind of: act, deed, human action, human activity.

is a broader term that covers: transmission | intercommunication | medium | channel, communication channel, line | mail, mail service, post, postal service | dramatic art, dramatics, dramaturgy, theater, theatre | discourse, discussion, treatment | exhortation | expression, verbal expression, verbalism | exam, examination, test | persuasion, suasion | dissuasion | expostulation, objection, remonstrance, remonstration | contact, touch | traffic ... show more.

derivation: communicate, intercommunicate | communicate, pass, pass along, pass on, put across | communicate | communicational.