trialogue
noun
tri·a·logue ˈtrī-ə-ˌlȯg 
-ˌläg
: a scene, discourse, or colloquy in which three persons share
Example Sentences
Recent Examples on the Web This leads directly to the topic of the value gap and the reform of EU copyright law, the likely final, decisive trialogue negotiations for which begin on Monday. 
Wolfgang Spahr, Billboard, 18 Jan. 2019 The council has sponsored trialogue programs, often featuring lectures by professors or religious elders, over the past two decades. Jonathan M. Pitts, baltimoresun.com, 20 May 2017
Wolfgang Spahr, Billboard, 18 Jan. 2019 The council has sponsored trialogue programs, often featuring lectures by professors or religious elders, over the past two decades. Jonathan M. Pitts, baltimoresun.com, 20 May 2017 Word History
Etymology
tri- + -alogue (as in dialogue)
First Known Use
1532, in the meaning defined above