[erichocean]

Reify is a general term, it means to "make concrete" (or to "make real" depending on the usage) something that is previously fuzzy or abstract.

When you make a concrete subclass of an abstract class, you are "reifying" that class. When you made the abstract class from the concept of something, you are "reifying" that concept.

It's a fun word.

[eigenhombre]

And, possibly, Clojurists are more likely to use the word, because of: https://clojuredocs.org/clojure.core/reify