As learned in elementary school English. what do you call words like -ation, -fy, -ing, -itis that you add to a word to form a derivative?

Wikipedia explains it best: A suffix is an "affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs."

Asked by Rachel Bortles · Last updated 4 years ago · 168.2K views · SOURCE