When experiencing a great time, usually when in the company of close friends. Where you announce to the group/friends that you are 'having a great time'.
in an awkward situation when you are with your partner and all his friends and you try to make best with his best girlfriend. you ask her if she's having a good time but subsequently making it more awkward!
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.
We have a Zoom meeting in a few minutes and I’ll probably go pajama casual.