Pronunciation IPA (key): /ˈsʌfɪks/ Audio (US)(file) Noun Singular suffix Plural suffixes (countable) A suffix is an affix that is added to the end of a word. In English this can change the meaning. Also, it can be required by grammar but not change the meaning; this could be to change the tense, the number, or for other reasons. Related words prefix affix infix Wikiwand - on Seamless Wikipedia browsing. On steroids.