What do we call two words that differ from each other by only one phoneme, such as met and mat?

What do we call two words that differ from each other by only one phoneme, such as met and mat?

• A. Minimal pair
• B. Allophone
• C. Phoneme
• D. Diphthong

Answer: (A)

Two words that differ by only one phoneme are called minimal pairs. met and mat share the same consonants /m/ and /t/ in the same positions, but their vowel sounds are different phonemes: /ɛ/ in met and /æ/ in mat. This single phoneme difference changes the meaning, illustrating a contrastive phoneme in the language. This is exactly what a minimal pair demonstrates: a pair of words that differ by one phoneme helps identify which sounds are phonemic in a language. An allophone would be a pronunciation variant of the same phoneme that doesn’t create a new word, so it wouldn’t form a pair with different meanings. A phoneme is the abstract category that distinguishes words, not the surface sound alone. A diphthong is a specific type of vowel that glides, not the relationship between two words that differ by one phoneme. So the best term for this relationship is a minimal pair.