i Register
In some senses, redditive is marked as obsolete, rare. Watch for register when choosing this word.
adj
Answering to an interrogative or inquiry; conveying a reply.
Restorative; relating to the process of restoring.
noun
A word which answers an interrogative.
AN Interrogative and its Redditive (i. e. the Word which answers it) shall be of the same Case and Tense[.]