Maas - what's it all mean?

[Steven Maas (CUTR)]

Now I'm thoroughly confused.  I had always assumed my family name came
from the river and/or village in the Netherlands.  Now I learn that in
Dutch it means loophole, and in Afrikaans it means a) mesh and b) runny
yogurt (yecch).  To muddy the waters yet further, here in Florida there
was a recently departed chain of department stores known as Maas Brothers,
named after the Jewish founders. 

The maas=mass explanation for Pynchon's use of the name seems unlikely to
me, although far be it from me to dismiss it out of hand.  I've seen that
unintentional misspelling a few million times (it seems like), and it
strikes me as a little lacking in subtlety.

Well the real meaning please stand up?