circumscription

noun

1. (countable, uncountable)The act of circumscribing or the quality of being circumscribed.
2. (countable, uncountable)Anything that circumscribes or a circumscribed area.
3. (countable, uncountable)The definition of what does and does not belong to a given taxon, from a particular taxonomic viewpoint or taxonomic system.

   “The circumscription in the APG system of the family Malvaceae includes the former families Bombacaceae, Sterculiaceae and Tiliaceae.”

4. (countable, uncountable)An electoral district; used often in texts treating electoral systems in Romance countries.