those of you scolding me into better behavior after my sixth use of the idiotic "rook!" title tag, I applaud your tenacity.
1. group of humans: one of the groups into which the world's population can be divided on the basis of physical characteristics such as skin or hair color
2. fact of belonging to group: the fact of belonging to a group of humans who share the same physical features such as skin color
4. biology strain of organism: a genetically distinct population within a species that may also be geographically isolated