Answer: Back-formation
Explanation:
Back-formation is a type of word formation that is distinct from others; it is not a normal way of forming word. In this type of word formation, words are formed by removing real or assumed affix from a word which already exists in the vocabulary. For example, the word babysit was derived from babysitter, edit was derived from editor
The word donate was derived from donation; donation ↔ donate
Hence, the word donate from gotten by back-formation from the word donation.
