A retrograde dictionary (German rückläufiges Wörterbuch) is a dictionary whose lemmas are ordered alphabetically according to their end (instead of their beginning). Exemplifying with the words of the current sentence:

A normal forward-ordered dictionary groups those words together that have a similar beginning, including, e.g., those that start with the same prefix. The purpose of a retrograde dictionary is to group together those words that share their termination. One can then find, e.g., all the items derived in the same suffix. (It can also serve as a rhyme-book.)

Given their purpose, retrograde dictionaries normally reduce to a mere word list. They are produced by using the word list of some general dictionary and outputting it in retrograde (not reverse!) order.

References

Brückner, Tobias & Sauter, Christa 1984, Rückläufige Wortliste zum heutigen Deutsch. 2 Bde. Mannheim: Institut für Deutsche Sprache.

Mater, Erich 2001, Rückläufiges Wörterbuch der deutschen Gegenwartssprache. s.l.: straelener manuskripte.