For Trym I found several pages who give a possible meaning as "uproar" or "crash" (in the sense of "load noise"), like this one:
http://en.wikipedia.org/wiki/Þrymr
However, nothing really convincing in the sense of authority...
I had myself tried to find something about Tiril earlier on, but had failed.
Rene
www.AboutNames.chThis message was edited 10/9/2009, 10:08 PM