What does shake it off mean?

While playing in a duos resurgence prematch, I got a shotgun kill and got a "shake it off" point bonus, like the place in the middle where it says +50 DOWNED and +? TEAM WIPED etc.

I got the normal along with +? SHAKE IT OFF.

I know might sound like a troll post if you haven't seen it before, but I am certain that I saw this and I couldn't find anything online about it. I'm afraid I was unable to take a screenshot of it.

I did have a friend. Maybe he did something at the same time as me or something?

The Shake it Off bonus points come from you getting a kill while under the effects of an enemy stun grenade.