affiks

Affiks, or afiks in Indonesian, are bound morphemes that attach to a word stem to modify its meaning or grammatical function. They are a core feature of many languages' word formation systems and occur in four main types: prefixes, suffixes, infixes, and circumfixes. A prefix attaches at the beginning of a word, a suffix at the end, an infix is inserted inside the stem, and a circumfix surrounds a word with both a prefix and a suffix.

Affixes serve diverse functions. They can be derivational, creating new words or changing a word’s category, as when -ness in happiness turns the adjective happy into a noun. They can be inflectional, signaling grammatical features such as tense, number, voice, or case without changing the word’s category. English examples include prefix un- and suffix -ed; Indonesian examples include me- and di-, which alter voice and derivation, or -kan and -i, which can indicate object or direction.

Morphophonemic changes often accompany affixation. Some prefixes trigger assimilation, so me- changes form depending on the following consonant (bawa → membawa, tulis → menulis, sapu → menyapu). In many languages, infixes are also attested; for example, some Austronesian languages insert an infix after the initial consonant to encode grammatical information. Circumfixes combine a prefix and a suffix around a stem, as in German ge- … -t for past participles (gearbeitet) or Indonesian di- … -kan to form certain passive or perfective meanings, as in dituliskan “to be written down.”

Affixation is a central topic in morphology and typology, illustrating how languages construct meaning and structure in compact word forms.