Contrast
A minimal pair consists of two forms with different meanings that differ in one sound in the same position. It is strong evidence that the sounds contrast in that language. English pin and bin distinguish /p/ from /b/. This modern example is a teaching comparison; it tells us nothing by itself about an unattested ancient pronunciation. Before declaring a contrast in a corpus, check spelling conventions, morphology, dialect, and whether the two forms truly share an environment.
Comparative example · Yoruba
Pitch changes meaning
In the WALS illustration, Yoruba /bí/ means “give birth”, /bī/ “ask”, and /bì/ “vomit”. The high, mid and low pitch levels are marked with different accents; tap each form to inspect the contrast. This is a modern comparison, not a claim about an ancient language.
Choose a form to inspect its tone mark.
Variants
An allophone is a phonetic realization of a phoneme conditioned by context or variation. English [pʰ] in pin and [p] in spin show why a chart of every audible sound is not identical to a phoneme inventory. Historical spellings can sometimes reveal such patterns, but a missing distinction in the script is not proof that speakers never made it.
Tone and prosody
Tone uses pitch patterns to distinguish lexical or grammatical forms. WALS gives Yoruba /bí/ “give birth”, /bī/ “ask” and /bì/ “vomit”, distinguished by pitch; these are modern-language comparanda. WALS also reports Ngiti kamà “chief” beside kámá “chiefs”, where tone participates in a number contrast. Read the accent marks as data, not decoration. Stress is prominence, tone is a pattern of pitch contrasts, and intonation spans utterances; they should not be conflated.
Modern-language examples on this page clarify a linguistic pattern. They do not establish unattested sounds or forms for an ancient language. Follow the cited sources below and keep editorial readings separate from the surviving trace.