"side conversation" is correct and usable in written English.
It refers to a conversation that is happening on the side or in addition to the main conversation or topic at hand. Example: During the meeting, there were several side conversations happening between colleagues, making it difficult for the presenter to be heard.
Through the years, one of his closest advisers has always been an Israeli and, in business meetings with others on his team, the two would occasionally slip into a side conversation in Hebrew.
In the context of recent polls which suggest social media is overtaking traditional channels as the preferred source of news, this isn't merely a biased side conversation, it's a complete whitewashing of your main news channel.
In any case, James Murdoch later acknowledged that, in fact, there had been more going on that night: he and Cameron, he admitted the following year, had discussed the BSkyB bid in "a tiny side conversation" which he couldn't really remember.
The side conversation takes place (sometimes) quietly among colleagues, even as someone else presents.
The overwhelming sound of call and response chants drowned out most side conversation, as protesters were forced by SCOTUS police to remain on the sidewalk.
If you do have to listen to their big presentation ensure that you look bored, leave the room half way through for a pee or start up a side conversation.
There's no reason to have side conversations.
Many side conversations were held between members of every possible combination of party and chamber.
Our Korean counterparts never hold side conversations in meetings as we do here.
Is it awkward resolving those side conversations you mentioned earlier? A. You know, it's not really, because I think people just know it's not right.
Should you? A. People sometimes do things in a virtual meeting that they'd never do in person, like checking sports scores or having side conversations.
