Ya gotta see the video ... Blac Chyna's standing in the terminal with her bodyguards when she yells at someone to get vaxxed and "stop being stupid, hoe!"

Folks who saw BC go nuclear in Miami International Airport tell TMZ ... the incident went down late Sunday night, and she was apparently set off by a fan's request for a picture.

We're told a lady holding a baby went up to Chyna to ask for the photo, and that's when BC started ranting about how the woman better be vaccinated.

Blac Chyna, BTW, is vaccinated ... she got her jab earlier this year while live streaming.

As you can see, most of the airline travelers just sit there in stunned silence ... and no one seems to react much to the animated, blue-haired Blac Chyna as she keeps going off. By the end of the rant, she's not even talking about vaccines -- instead, she was going off about her Washington, DC roots. 🤷🏽‍♂️