Our group was split from Chikayama-Taura laboratory, whose domain name was 'logos,' which is an ancient greek philosophy terminology meaning 'logical things.' It was so chosen because the main focus of Chikayama group when it was launched was logic programming languages.
We followed this tradition instead of a more common method (at least in Japanese universities) that names its domain name after the leading professor's initial letter. In my case, it would have been 'tl' (for 't'aura 'l'aboratory), which is a kind of too obvious.
Our domain name 'xxx' is a greek philosophical word meaning 'yyy'. The choice of this particular word is somewhat arbitrary :-), but it was determined by discussion and voting from the initial members of the laboratory. Here you can trace it