Taxonomy is all about organizing and classifying. To make it sound more scientific, you could refer to your project of reorganizing your spice rack according to smell as a taxonomy of spices.
Taxonomy is a word used mainly in biology to talk about classifying living organisms, organizing them according to their similarities. If you've ever seen a chart with animals divided into species, genus, and family, you know what scientific taxonomy is. The word comes very straightforwardly from Greek words for "arrangement" — taxis — and "method" — nomia. So any special method for arranging or organizing things can be called taxonomy.