# affix

/ˈæfɪks/ (US)

Source: https://englishreference.com/word/affix
Updated: 2026-08-27

## Senses

### 1. to attach

verb · CEFR B2 · Formal

to stick, fasten, or attach something to something else.

For teachers: to attach, fasten, or stick one thing to another. Transitive; requires a direct object and often takes the preposition 'to'.

- You must affix a recent photograph to your visa application form.
- The technician was instructed to affix the warning labels to the exterior of the machinery before it left the factory floor.

Usage: Typically used in administrative or technical contexts rather than casual conversation.

### 2. linguistics

noun · CEFR C1 · Technical

a group of letters added to the start or end of a word to change its meaning.

For teachers: a bound morpheme attached to a stem or root to form a new word or word form. This category includes prefixes, suffixes, and infixes.

- In the word 'unhappy', the letters 'un' are a negative affix.
- The professor explained how the addition of a derivational affix can change a word's grammatical category from a verb to a noun.

Usage: Countable noun used primarily in the study of language structure.

### 3. mathematics

noun · CEFR C2 · Technical

a way to show a complex number as a point on a graph.

For teachers: the complex number a + bi corresponding to a specific point (a, b) in the complex plane.

- The student plotted the affix on the Gauss plane during the geometry lesson.
- In complex analysis, the affix represents the coordinates of a point within the Argand diagram.

Usage: Highly specialized term used in complex number theory.

## Examples

- The affix "re-" means to do something again.
- Adding the affix "-ness" to the adjective "kind" creates the noun "kindness".
- While English predominantly uses suffixation, the language permits multiple affixes to stack, as in "un-believ-able-ness", where each successive bound morpheme alters the grammatical category or semantic value of the stem.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.