It’s very interesting to know that nobody would be using the exact meaning of ambulance in Hindi because hardly few people would know–in conversational Hindi, I can estimate on a daily basis you will hear 20-80% words that are not originally from Hindi language.
Ambulance is called ambulance–एम्बुलेंस in Hindi, though it has its own name and meaning in Hindi too.
Sometimes, it is simply called hospital van, but if you are really looking for its original Hindi meaning, it is this:
|Ambulance||रुग्ण वाहिनी||Rugṇa Vāhinī|
The meaning of this Hindi word is a vehicle that carries the patients.