Need help finding the correct spelling of my Cantonese name!

Hi

So long story short:
I have a grandfather from Hong Kong, he moved to the UK a long time ago and he's the only one that speaks Cantonese in my family. When I was born, my parents asked him to pick a Cantonese middle name. The only problem was that he doesn't write or speak English very well at all as amongst other things, due to a pretty horrific childhood he never went to school. So he phonetically sounded out the word/s 'Joiwan', and my young parents basically just guessed an English/phonetic spelling.

So my middle name is Joiwan, and I was told all my life that it was Cantonese and meant something like 'fluffy cloud'. I've only just found out that the spelling was guessed, and laughably I actually feel quite upset about it. I felt like my name was my only link to a heritage that I felt really proud of, and now I find that 'Joiwan' doesn't actually mean anything at all!

Sorry for the essay, I was just hoping that someone might be able to shed some light on what the correct phonetic spelling might actually be. So to repeat:
(Incorrect) phonetic spelling: Joiwan
Rough meaning (I think): Fluffy cloud

Thank you in advance!