where might i find a general to specific dictionary?

Question

I'm looking for a dictionary that, unlike a normal alphabetically organized dictionary, has its words organized from a general to specific order. For instance, there might be one category called nature with subcategories of living things, the earth, and the human body that increasingly get smaller. A thesaurus comes close but it’s not quite right.

Answer 1

a table of contents is organized this way at the beginning of a book

Answer 2

Sounds to me as if you really want an encyclopedia. Encyclopedia are weighty tomes of immense value to the scholar in that you are able to find these dedicated to a specific theme or discipline. The ideal place to find this wonderful aid to education is what we Earthlings call a Public Library. You can generally find one -or more- in each and every town and city in this awesome country!