1) This is any system of organisms or things ranked one above another.

Explanation:

Ranking a system of organisms (plants or animals) or things (non living entities) one above another is using a a hierarchical classification.

Classifying organisms in species, genus, family, order, class, phylum, kingdom and domain (the taxonomic rank) is following a hierarchy.

The hierarchy consists in that the species in the highest rank encompasses the species in the immediate lower rank.

Thus, the system takes the shape of a pyramid. An inverted pyramid in the case of the taxonomic rank: the domain is the biggest level and is on the top, the species is the lowest level and is at the bottom.