Talk shop
Definition 1 of 1
Pro Tip 1/3Social Context
Used in casual settings among colleagues. May not interest others outside the work field. 
At the family BBQ, Mike’s friends quickly got bored when he started to talk shop.
Pro Tip 2/3Time Off
Often happens during breaks or social gatherings, not during actual work hours. 
They went out for lunch and couldn't resist talking shop over their meals.
Pro Tip 3/3Subject-Specific
The topics are usually inside jokes or detailed matters understood by peers in the same field. 
Even at the potluck, the engineers gathered in one corner and talked shop.