vries means freeze. even though not used like that specifically, you are right in your thought that vries means freeze. "ik vries" -> "i freeze".
friesland's name is disputed though between being founded by a guy named 'friso' and that 'Fries' means 'peoples with curly hair' :D - so much for logic & linguistics :D!
Which is why I didn't want to go into the actual etymology, because the only reason it was a fun fact is because the current meaning of the word is freeze, regardless of what it referred to in the past :)
