the basics
In the previous chapter, we learned about the actual, physical nature of speech sounds. Phonology is more abstract than actual, because phonology attempts to describe the complicated notion of how phonetic speech sounds function within a given language. Describing what something is (phonetics) is a bit easier than describing what something does (phonology), especially when what you are attempting to describe is something as complicated as human language.
Nonetheless, that is the task at hand. First, we have to understand some new concepts.
phonemes
The first concept to tackle is the phoneme. In spoken language, a phoneme is an abstract speech sound or group of speech sounds which are distinguished by a native speaker as having the same meaning.
In the definition above, we see the word "abstract" because a phoneme is a mental construct, not an actual sound. You may recall that the speech sounds (or phones) that we discussed in the phonetics chapter were the actual, you-can-hear-them sounds; phonemes are the symbolic, written representations of those sounds.
For example, /b/ is a phoneme that symbolically represents the sound we create when we speak the second letter of the Roman alphabet. In other words, the phoneme /b/ is a symbol enclosed between two slashes, that describes a quality of "B-ness" that we hear when someone speaks a voiced, bilabial oral stop, not the actual sound itself.
By the way, whenever a linguist is describing phonemes, he or she will use slash marks, / / , to enclose the symbol for the phoneme.
You may be wondering, "If a B sound (phone) has a B symbol (phoneme), why not just use the regular alphabet letters to write about speech sounds instead of all this complicated phonemes business?" One reason is because in linguistics, we are usually working with the International Phonetic Alphabet, not the Roman alphabet, and the first is much more complicated and comprehensive than the second.
This makes more sense of you peek at an English pronunciation chart. In the case of the abstract, written phoneme /b/, in English there happens to be only one way to pronounce it, [b], as in the first sound in "boy." If only the rest of our speech sounds were so simple...
Alas, they're not. Consider this: What if you had a friend in Brazil who was studying English, and she emailed you asking you to explain how to pronounce the word "thy." What Roman alphabet letter(s) would you use to write a description of the sound at the beginning of the word? You couldn't use th with any guarantee your friend would know what sound you were describing, because there is more than one way in English to pronounce the written combination of the letters th, and if you mix them up your change the word's meaning and pronunciation. For example, repeat the words "thigh" and "thy" slowly, and you will hear that they sounds different, because the first is voiceless (vocal cords don't vibrate), and the second voiced (vocal cords vibrate).
If your Brazilian friend has studied linguistics, however, you need not fret. When linguists created the International Phonetic Alphabet, they created a phoneme based on the Greek letter theta, /Θ/ , to represent the voiceless sounds like the one at the beginning of "thigh", and another phoneme, based on the Old English, lower-case letter D (called an eth), /ð/, to represent the concept of the voiced sounds like the one at the beginning of the word "thy."
And so it is that /Θ/ is a phoneme that succinctly means "having the quality of a voiceless interdental fricative" and /ð/ is a phoneme that means "having the quality of a voiced interdental fricative." Linguists agreed upon this when they adopted the International Phonetic Alphabet, so when they read those phoneme symbols they know exactly what sound they represent.
allophones
Another complicated term used in phonology is
allophone. An allophone is one of several similar speech sounds belonging to a phoneme. Each allophone is the form of the phoneme used in a specific context.
By the way, whenever a linguist is describing actual sounds of a phoneme, he or she will use brackets, [ ], to let you know he or she means actual, you-can-hear-them allophones.
It will be helpful to look at the definition of a phoneme again: "a phoneme is an abstract speech sound or group of speech sounds which are distinguished by a native speaker as having the same meaning." Let's pay close attention to "group" and "distinguished," because those concepts relate to allophones.
The simplest way to see how phonemes and allophones are related is to pick two words that have only one unique sound difference, like "bin" and "pin" (these types of almost-identical pairs of words are called minimal pairs). Do they have the same meaning? They do not, so they are distinguishable. What makes them distinguishable? It has to be the first phonemes of the word, /b/ and /p/, because that's the only difference. The chart below lists some more examples of minimal pairs.
To see a full-size image of the minimal pairs chart, or to print a copy for your class notes, click here for the Adobe PDF version.
But sometimes, you can change a sound in a word and not change the meaning. This is a clue that you are speaking or hearing allophones, the individual sounds that can be grouped together and defined as a single phoneme. For example, [ph] as in "pill" and [p] as in "spill" are the two allophones that group together under the phoneme /p/ in the English language. English speakers generally treat these as the same sound, but listen carefully and you can hear that there's a subtle difference. The initial [ph] in "pill" is aspirated. If you hold your hand in front of your mouth, you can feel a relatively strong puff of air when you speak it, that's aspiration—but the latter, the [p] in "spill", is unaspirated. It sounds a little more like the B of English.
So [ph] and [p] are not exactly the same, yet they are so close that they are both classified as voiceless bilabial oral stops on the English pronunciation chart.
For an example of allophones in vowels, listen carefully when you talk to someone who has a different dialect than you do. The way they pronounce their vowels may sound odd, but you probably can still clearly understand them. Their vowel sounds are different, but not so much so that they change the word's meanings. Ah-ha! Sound differences that can be grouped together, because they don't change the meaning—our clue that allophones are at hand.
You are both using the same vowel phonemes /a/, /e/, /æ/, and so on. But if you are listening to a person from, for example, Wisconsin, you may hear allophones of the phoneme that have heavy nasalization. You may use the allophone [a] (the lowest, back vowel), which is an allophone of the phoneme /a/, when you say a word like "bomb," while the Wisconsinite is using the allophone [ã] (the tilde mark means it is nasalized), which is just another allophone of the phoneme /a/, when they say a word like "bomb."
