A sound unit that can change one word into another in a given language.
In precise terms
A contrastive unit of the sound system of a particular language, established by the existence of minimal pairs. Phonemes are language-specific abstractions, conventionally written between slashes: /p/, /b/.
An example
pin /pɪn/ vs bin /bɪn/
What is going on here
Swapping /p/ for /b/ changes the word, so English treats them as separate phonemes. The two sounds differ only in voicing. In a language where that difference never distinguishes words, the same two sounds would not be separate phonemes.
Why this matters when you are learning a language
Your ear was trained by your first language to hear its phonemes and to ignore differences that language does not use. That is why some target-language contrasts are genuinely inaudible at first — the problem is categorisation, not hearing.
Across languages
Korean distinguishes three series where English has two, so English /p/ and /b/ both map awkwardly onto the Korean system. Mandarin contrasts aspiration rather than voicing. Hawaiian has one of the smallest phoneme inventories recorded; several languages of southern Africa have among the largest.
Related terms
- Minimal pairAdvanced — Two words or signs with different meanings that differ in exactly one sound or sign parameter.
- AllophoneAdvanced — One of the predictable pronunciations of a single phoneme, chosen by its environment.
- SyllableAdvanced — A sound unit organised around a central peak, with optional sounds before or after it.
- StressAdvanced — Extra prominence given to one syllable relative to nearby syllables.
- ToneAdvanced — A language-specific pitch pattern on a syllable or word that can distinguish meaning.
- MorphemeAdvanced — The smallest unit of a language that carries meaning or grammatical function.
- MarkednessAdvanced — The idea that one member of a grammatical pair is the basic, default one and the other is the special case.
Where to go next
- Pronunciation guides
- The IPA
- Notation systems — How linguists write these distinctions down — the IPA and its relatives.
- Terminology quiz — Test the terms on this page.