WordPlay uses Natural Language Processing (NLP) to find semantically similar words to the input. For example, cat would return: dog, rabbit, monkey, rat, etc.
WordPlay can also solve analogies using linear combinations of words. Enter A - B + X to solve analogies of the form B is to A as X is to ??
For example, paris - france + germany should return berlin
(France is to Paris as Germany is to Berlin).
Other analogies you can try include: king - man + woman, backpack - school + office, or dancer - dance + art