Colloquy
/ˈkɑːləkwi/
Definition 1 of 1
Pro Tip 1/3Serious Tone
The word 'colloquy' often implies a discussion with a thoughtful, earnest tone, not casual chat. 
The two philosophers were deep in colloquy, barely noticing the time passing.
Pro Tip 2/3Formal Context
'Colloquy' is used in formal or academic settings, rather than everyday conversation. 
During the conference, there was a colloquy on the latest scientific research.
Pro Tip 3/3Limited Participants
A colloquy usually involves two people, but can sometimes include more, focused on close communication. 
The director entered into a colloquy with the lead actors about the film's vision.