circumscription

noun

1. 1

   The act of circumscribing or the quality of being circumscribed.

2. 2

   Anything that circumscribes or a circumscribed area.

3. 3

   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. 4

   An electoral district; used often in texts treating electoral systems in Romance countries.