"mein" means noodles in
Chinese, as in
Chow Mein. Its Japanese equivalent would be "men", as in
ramen. Its Korean equivalent would be "myun", as in
jajang myun.
It's pronounced 'meen' in Cantonese.
There is a distinction between 'noodles' (egg-based) and 'rice noodles' (rice-based). Regular egg-based noodles are called "mein" whereas rice noodles are called "fun", as in Chow Fun. There is also a distinction between "fun" and "faan" (which sound approximately the same in Cantonese). "Faan" is rice.