field / region / area / domain (taxonomy)
域
=
土
+
或
:
Yu the Great (yu) and Osvaldo Farrés (或) have been working in the space station's bathroom (Ø4) for several days now. Their task is to classify different kinds of mud (土) and build a mud taxonomy (域). Most of the time they slack off and play games through the LAN (域) instead, though.