Phone (phonetics)

Phones versus phonemes

Phones are the segments of speech that possess distinct physical or perceptual properties, regardless of whether the exact sound is critical to the meanings of words. Whereas a phone is a concrete sound used across various spoken languages, a phoneme is more abstract and narrowly defined: any class of phones that the users of a particular language nevertheless perceive as a single basic sound, a single unit, and that distinguishes words from other words. If a phoneme is swapped with another phoneme inside a word, it can change the meaning of that word. Said another way, switching one phoneme to another phoneme inside a word will change that word into another word (or into nonsense).

For instance, the phone in the English word hick, a word transcribed as in the International Phonetic Alphabet (IPA), distinguishes it from other words, like hit, hip, hiss, hitch, etc., suggesting that belongs to a phoneme in English. The English words kid and kit, and in the IPA, end with two distinct sounds (phones), and , and swapping one for the other makes the one word sound like the other. Thus, in the English language, these particular phones are classifiable under two separate phonemes, transcribed as versus (slashes indicate phonemes in the IPA, while square brackets indicate phones). However, the difference between the sound in some dialects' pronunciation of sheet and the in shack ( versus in the IPA) never affects the meaning or identity of a word in English. Even if those particular phones are interchanged, those two words would still likely be recognized as sheet and shack by native English speakers. Therefore, the phones and do not belong to two separate phonemes in English; rather, they could be classified as two possible phonetic variations (called allophones) of the same phoneme. In contrast, languages other than English, such as some Slavic languages like Polish or Russian, may indeed perceive and as separate phonemes.

As another example, swapping the sounds and in the English word spin does not change its meaning. However, in Hindustani (Hindi and Urdu), swapping these phones can change one word into another: for instance, (फल/پھل) means 'fruit', and (पल/پل) means 'moment'. The sounds and are thus different phonemes in Hindustani but are not usually considered distinct phonemes in English.