suffixions

/səˈfɪkʃənz/
noun
  1. The act or process of adding a suffix to a word.
    • The suffixions of '-ness' and '-ity' are common in English.
    • Linguists study suffixions to understand how languages evolve.
    • In the classroom, the teacher explained suffixions using examples like 'happy' becoming 'happiness'.
Synonyms