An ELT Glossary : Affix / Affixation

  • Definition : Affixation is the morphological process of adding an affix to the stem of a word (a free morpheme), thus modifying its meaning and/or changing its word class. An affix is a bound morpheme (part of a word with recognisable meaning/use which cannot stand alone) 
  • Examples : a)  "un" as in unhappy : the affix changes the meaning of the free morpheme happy from positive to negative; b)  "ly" as in quickly : the affix changes the form of the free morpheme quick from  adjective to an adverb.
  • As these examples show, in English affixes may occur at the beginning of a word - eg unhappy - in which case they are called prefixes, or at the end - eg quickly - in which case they are called suffixes. In other languages, they may also occur in the middle, in which case they are called infixes (eg in Tagalog the past tense marker -um- : sulat = to write , sumulat = I wrote)

Further reading

Gairns and Redman, Working with Words, Cambridge

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