morphemes & allomorphs

You may notice that the word morpheme resembles phoneme, and allomorph resembles allophone. Ah-ha! For all you right-brained-dominated scholars, we offer this Venn diagram:

Let's describe the same idea here for the left-brainers. You may recall that in the phonology chapter we defined phoneme as an abstract speech sound or group of speech sounds, with allophones as a sub-category. Similarly, morpheme is the general classification, and allomorph the sub-category. That's the general relationship.

Morphemes are meaningful and indivisible units in a given language.

First, let's look at the operative word meaningful in the above definition. The phonemes /k^h/, /æ/, and /t/ are used in the word cat [k^hæt], and each one is as small as they come, but they are not morphemes. Why? Because they are not "full of meaning." All these three particular phonemes do is help us think of three specific speech sounds—they don't have meaningfulness in the sense of defining anything other than themselves.

So if the above phonemes are not "the smallest meaningful unit in a given language," what is? Let's answer that by looking at the three morphemes in the word "meaningful." They are mean + ing + ful. "Mean" is a morpheme with a sense of signification or representation; "ing" is a morpheme that means, in this context, an instance of a process or action; "ful" is a morpheme that means, in this context, characterized by or resembling.

Note that all three of the above morphemes are listed in the dictionary. If you are ever unsure whether or not a word segment is a morpheme, consult a dictionary. If the word segment gets its own listing, like the examples above did, then you can be assured it's a morpheme.

Now let's look at that word "cat" again to learn more about the indivisible part of the definition for morpheme. As we learned, there is only one morpheme in the word "cat"—the whole word is a single, indivisible morpheme. "C" by itself doesn't mean anything; "ca" doesn't mean anything; "at" doesn't mean anything in this context—the context we apply in defining morphemes is just within the word itself, not the entire language the word is a part of. But all three sounds together, [k^hæt], that does have meaning: an animal, a feline, etc. Since "cat" is an indivisible unit in English for conveying a meaning, it is a morpheme.

Allomorphs are the variant forms of an identical morpheme.

For example, let's take the word "cats." We already determined that "cat" was a morpheme, but we have another morpheme added to it, cat + s. "S" is a morpheme, because it has meaning in this context—more than one—and it cannot be broken down any further.

In English, there are other morphemes that mean "more than one." Cats, dogs, horses, and oxen all have a different morpheme that means "more than one" at the end of them. Cat + [s], dog + [z], horse + [əz], ox + [ən]. So, [s], [z], [əz], and [ən] are all allomorphs of the same morpheme. All four allomorphs sound different when you pronounce them, and they are represented by different phonetic alphabet symbols, but they all have the exact same meaning, so they are allomorphs.

types of morphemes

The millions of morphemes in English are divided into two major classes, free morphemes and bound morphemes.

A free morpheme has to pass two tests:

• it has to be a content word
• it cannot contain any other morphemes

The word "language" is an example of a free morpheme. It is defined in the dictionary as having lexical meaning, and it cannot be divided into any other morphemes.

A bound morpheme is defined by three qualities:

• it is not a content word
• it is always bound to another morpheme, either a free morpheme, or sometimes another bound morpheme

The word "languages" is an example of a combination of [free morpheme] + [bound morpheme] = [language + s]. "Language" is a free morpheme, and "s" is a bound morpheme.

Don't forget the importance of context in defining morphemes. The suffix "s" on the word "language-s" is a morpheme because it has meaning in the context of the words itself—plurality, more than one. As a contrast, the [s] in "sheep" is NOT a morpheme, because it has no independent meaning other than defining a speech sound, /s/.

Derivational morphemes create a new word when added to another morpheme. For example, "read" is a free morpheme. Add the derivational suffix -er to the end of it, and you get "reader," which is a [free morpheme] + [derivational morpheme] = [a newly derived word].

You can confirm whether or not a morpheme is derivational by consulting a dictionary. If you can find an individual entry for your free+bound morpheme—not just an extension of another word's definition—then the bound morpheme you added to the other morpheme was derivational, because when added it derived a new word from the old one.

Looking at the word "reader," you can see that it is indeed a different and unique dictionary entry compared to "read," so it meets the test to be a derivational morpheme.

Inflectional morphemes do not derive a new word when added to another morpheme—they only change the word's grammatic properties such as tense, gender, and case. For example, "read" is a free morpheme. Add the inflectional suffix -s to the end of it, and you get "reads," which is a [free morpheme] + [inflectional morpheme] = [the past tense of a word].

You can confirm whether or not a morpheme is inflectional by consulting a dictionary. If the process is [free morpheme] + [inflectional morpheme] = [a different word], but when you check a dictionary you only find a listing for the different word as part of the listing of the [free morpheme's] definition, then the bound morpheme you added to the other morpheme was indeed an inflectional.

advanced study

The examples of morphology above are simplified to help you grasp the basic concepts. Most words are more complicated than those we have been discussing. For example, the word from the top of this page, antidisestablishmentarianism, is a combination of several morphemes. For a challenge, try to divide this word into its morphemes and define each segment as a free, bound derivational, or bound inflectional morpheme.

Morphology also studies the numerous ways new words are formed. Many neologisms recycle familiar morphemes into new combinations. Some words are entirely new. Merriam-Webster's website has a terrific explanation of the etymology of English words.