Lexical Morphology

A language's lexicon (vocabulary) comprises words and parts of words that carry different meanings. These meaningful units of language are referred to as morphemes. The study of morphemes in a language is known as morphology. In general, morphology is concerned with how words are created, the structure of words, and how word structure can affect meaning. One type of morphology is lexical morphology.

Lexical Morphology Introduction

Lexical morphology is a specific type of morphology that refers to the lexemes in a language. A lexeme is a basic unit of lexical meaning; it can be a single word or a group of words.

Lexical morphology is the study of lexemes and how they are created. The discipline is particularly interested in neologisms (newly created words from existing words), derivation, and compounding.

Derivation in Lexical Morphology

Derivation refers to a way of creating new words by adding affixes to the root of a word - this is also known as affixation. In case you need reminding: "affix" is a broad term used to refer to a morpheme added to the beginning or end of a root word. Affixes are known as bound morphemes, meaning they must be attached to another word as they do not make sense on their own.

There are two types of affixes: prefixes and suffixes.

Prefixes are placed at the beginning of a root word to change the word's meaning (e.g., the "re" in "reapply").

Suffixes are placed at the end of a root word to change the word's meaning (e.g., the "ful" in "hopeful").

When affixes are used to create new words with new meanings, they are referred to as derivational affixes. When they are used to create different forms of the same root word (such as to show changes in tense or plurality), they are referred to as inflectional affixes.

Fig. 1 - Impossible is an example of derivation.

Compounding in Lexical Morphology

Compounding refers to the creation of new words by combining two or more existing words together.

For example, the nouns "bed" and "room" can combine to create the compound noun "bedroom." It is important to know that compound words do not always have to be nouns. For example, there are also compound adjectives, such as "long-term, "quick-witted," and "rose-tinted."

Fig. 2 - Bedroom is an example of a compound noun.

Lexical Morphology Examples

Both derivation and compounding are significant parts of lexical morphology as they are a large source of new words in the English language. Below are some examples of derivation; including the original root words and the types of affixes added to create the derivation:

Now here are some examples of compounding:

• Green + house = Greenhouse

• Mother + in + law = Mother-in-law

• Motor + bike = Motorbike

• Cook + book = Cookbook

• Foot + ball = Football

• Sky + scraper = Skyscraper

• Skate + board = Skateboard

Lexical Morphology Structure

Lexical morphology looks at the structure and form of lexemes. A lexeme can have many different inflected forms, meaning the word can be changed in order to indicate a grammatical role in a sentence, such as to show plurality or tense. For example, take the lexeme "walk." The inflected forms of this verb are:

• Walked

• Walking

• Walks

These are all different forms of the same lexeme; walk. To create these forms, suffixes have been added to the end. Keep in mind that the noun "walker" is NOT an inflected form of "walk" - it is a separate lexeme as it is a different word class.

Lexical Morphology Theory

Lexical Morphology can also refer to the theory first put forward by Pesetsky in 1979 and later developed by Kiparsky in 1982¹.

It is worth mentioning that there is not only one lexical morphology theory to follow, but each theory contains the key idea that both phonology rules and morphology rules work together when building the lexicon (vocabulary) of a language.

So what is phonology, and how does it work alongside morphology?

Both phonology and morphology look at patterns in language and how they create meaning; phonology focuses on the sounds (phonemes) in a language, whereas morphology focuses on the formation/structure of words (morphemes) in a language. They must both combine in order to communicate, as written and spoken words correlate with one another.

Without morphological rules, we would be unable to create new meaningful words. Without phonological rules, we would be unable to comprehend the sounds that letters make, so we would therefore be unsure how to pronounce written words or spell spoken words.

The relationship between phonology and morphology (and how they affect one another) can also be understood by looking at the Level Ordering Hypothesis, which is further discussed below.

A key model to be aware of when looking at the lexical morphology process is the Level Ordering Hypothesis, originally developed by Siegel (1974).² The hypothesis aims to show that affixation occurs in two different classes.

The different derivational affixes in English can be broken down into class 1 and class 2 affixes.

• Adding a class 1 affix to a word causes a change in the phonological process (particularly the stress pattern) of a word.

• Adding a class 2 affix does not change the stress pattern.

Another example is as follows:

Fig. 3 - Affixation is the addition of affixes to a word.

¹Paul Kiparsky. Lexical Phonology and Morphology. 1982.

²Dorothy Siegel. Topics in English Morphology. 1974.