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6.2: The mental lexicon

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    • Catherine Anderson, Bronwyn Bjorkman, Derek Denis, Julianne Doner, Margaret Grant, Nathan Sanders, and Ai Taniguchi
    • eCampusOntario

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    In the previous chapters, we looked at some of the regularities that occur in language: predictable patterns that are rule-based. For example in English, the plural -s /z/ turns into [ɨz] after sibilant (= high pitched, hissy) consonants. That’s a regular pattern, because if you encounter a count noun that ends in a sibilant consonant, we can predict that the plural marker would be realised as [ɨz]. You can tie regularity to predictability: if something is predictable, it’s a regular rule. Imagine that a new beverage called Loquesh [lowkwɛʃ] was invented in Canada. Even though you have likely never heard this word before in your life, you can still predict that if we pluralised it using regular English plural morphology, it would be pronounced [lowkwɛʃɨz] and not *[lowkwɛʃz] or *[lowkwɛʃs]. The regular rules in your mind as a language user is a part of the language user’s grammar (or mental grammar; see Chapter 1).

    Some things in language, however, are not predictable like this. Some things are irregular. For example, consider the morpheme goose. The fact that the stream of sounds [ɡuws] (goose) refers to the large waterbird with a long neck is not a predictable pattern in English. As discussed in Chapter 1, this connection between the pronunciation and the meaning is arbitrary. It’s not that the sound [ɡ] means ‘long neck’, [uw] means ‘water’, [s] means ‘beak’, etc.: we just happen to use this combination of sounds to refer to this animal in English. If the sound-meaning connection were meaningful, we would expect that a similar sequence of sounds would be used in all languages to refer to a goose. But this of course does not happen. In Ojibwe it’s nika [nika], and in French it’s oie [wa], for example. Sign-meaning correspondences of morphemes are irregularities in language, because you simply must memorise the fact that in your language community, certain sequences of sounds/signs mean certain things. These irregularities — the things that cannot be predicted by rules — are stored in your lexicon, which is a part of your mental grammar or linguistic competence.

    Morphology recap!

    A free morpheme is a morpheme that can stand on its own as a word. A bound morpheme is a morpheme that cannot stand on its own as a word.

    The lexicon (also sometimes called the mental lexicon in this context) is a language user’s mental storage of that linguistic information that cannot be captured by rules. So this means that the lexicon stores linguistic units whose meaning cannot be predicted from its subparts. Meaning that cannot be predicted from its subparts is called non-compositional meaning. For example, free morphemes like goose, luck, and go in English have non-compositional meaning; you can’t break down its meaning into smaller parts. Therefore, they get stored in the lexicon. Affixes also have non-compositional meaning, so morphemes like -s, -ly, un-, -er, and so on also get stored in the lexicon.

    Idioms are stored in the lexicon too. Over the moon is an example of an idiom: it is a meaningful sequence of words, but the meaning is not compositional.When someone says that they are over the moon, they likely are not literally over the moon; in spoken North American English, this means that this person is extremely happy. Because this idiomatic meaning of over the moon does not break down into the meaning of over, the meaning the, and the meaning of moon, the meaning of this idiom is non-compositional. It’s important to remember that different language communities have different idiomatic phrases. In North American English, piece of cake is an idiom that means ‘easy’. But if you say in Japanese ke:ki hito-kire ‘cake one-slice’ (literally ‘piece of cake’) with the intention of saying that something is easy, you are not going to be successful. A Japanese speaker may use the idiom asameshi-mae ‘breakfast-before’ (literally ‘before breakfast) to express that something is easy, though! In American Sign Language, TRAIN GONE SORRY (as shown below) is an idiom that roughly means ‘you missed what was said, and I’m not going to repeat it.’ In French, the phrase les carottes sont cuites (literally ‘the carrots are cooked’) means ‘it’s too late, there’s nothing more you can do’. In each language community, there are different idioms.


    Figure \(\PageIndex{1}\). TRAIN GONE SORRY (American Sign Language)

    Under the same reasoning as idioms, it can be said that non-compositional compounds like hotdog (it’s non-compositional because a hotdog is not a dog that is hot) are stored in the lexicon, too. Compositional compounds like dog leash are probably not stored in the lexicon: dog would have its own entry and leash have its own separate entry.

    Other things not stored in the lexicon are words like skater, unluckily, reclassify, and other multimorphemic words. These words have compositional meaning because their meaning is predictable from their subparts: skate and -er for skater; un-, luck, -y, and -ly for unluckily, and re-, class, and -ify for reclassify. The idea is that you don’t have to “memorize” what unluckily means. You memorise the meaning of un-, the meaning of luck, the meaning of -y, and the meaning of -ly separately — and then morphosyntactic rules in the grammar put them together as unluckily. Similarly, phrases and sentences with compositional meaning are not stored in the lexicon, either. For example, a phrase like over the candle (as in I placed a jar over the candle) is not stored in the lexicon, provided that it is not an idiom in that language community.

    We will use the term listeme to refer to anything that has a lexical entry in the lexicon. This is an umbrella term that includes morphemes, idioms, and some compounds. They are called listemes because they are listed in the lexicon. Each listeme in the lexicon has a lexical entry, which contains the linguistic expression’s phonological, syntactic, and semantic information. So for the lexical entry of goose, it lists its pronunciation (/guws/), its syntactic category (noun), and of course, its meaning, or the sense of that listeme.

    Note that the mental lexicon is not like a literal dictionary, so some things you find in a dictionary entry are not necessarily found in a lexical entry. For example, if a language has a writing system, some users of that language may know how words are spelled. However, spelling is not something you have to know in order to be a language user. Have you ever spoken to a 5-year old? Children are language users, too! It’s entirely possible for children to use words accurately in conversations without knowing how to spell the words. This is why we will not discuss spelling as a part of lexical knowledge in this chapter. The etymology of the listeme is not something you necessarily know when you “know” the listeme, either. If you are a word history enthusiast, you might know that goose comes from Old English gōs, but certainly a 5-year old would not know this (many adults don’t, either!). Unlike phonology, syntax, and semantics, etymology is not something you naturally pick up when you are first learning a word. For this reason, we will also exclude etymology from our discussion of lexical knowledge in this chapter.

    Some linguists say that irregular inflected forms of words are stored in the lexicon, too. For example, the past tense of go is not *goed, but rather went. The plural form of goose is geese, not *gooses. Since expressions like went and geese are irregular patterns that must be memorised, it can be hypothesised that they have their own lexical entry in the lexicon, too.

    To summarize, the lexicon is the storage of irregularities in a language. Each lexical entry in the lexicon comes with a listeme’s phonological, syntactic, and semantic information. This leaves us with the big question of this chapter: what goes into the semantics of a lexical entry? What even is word sense? We will begin to address this in the next section.

    How to be a linguist: Whose lexicon?

    It’s important to remember that even within one language community, one language user’s lexicon may not be exactly the same as another language user’s lexicon. For example, my brother and I are both Japanese speakers, but there may be some words he knows that I don’t know, and vice versa. But when I compare my Japanese lexicon to my brother’s lexicon, there is enough overlap that we are able to communicate with each other. As a Japanese-American individual who grew up speaking both Japanese and American English, I occasionally find that the meaning of some words in my American English lexicon are different in specific ways from the meaning that other American English speakers have. I’ve gotten funny looks from people for calling green traffic lights in Canada blue. Ao in Japanese is typically translated as ‘blue’, and for the most part it points to the same shade that the English word blue points to. But ao is also used to describe “green” things sometimes, including green traffic lights, green apples, and vegetables. Because of this, I have the impulse to call traffic lights blue in English. It is entirely possible that my lexical representation of the word blue in English is not the same as that of many Americans. It is also equally possible that not all Japanese-English bilinguals have the same representation as I do! Does this mean that I have the “wrong” meaning of blue stored in my head? I don’t think so. It just happens to be the case that blue means a certain thing in my idiolect. In this chapter, we use commonly attested linguistic data to make inferences about lexical meaning at a general level. So in this textbook you won’t find me discussing how blue in English can also mean ‘green’. But I’d like to explicitly acknowledge here that semantic variation exists, in the same way that phonological, syntactic, and morphological variation exist. So for example, in this chapter I might say “she is very alive is descriptively well-formed in Canadian English”, but it is entirely possible that some people will find it ill-formed in their dialect or their idiolect. Where semantic variation is especially common, notes will be made — but in general, know that it’s OK if your judgment varies, and that your idiolect is valid. When you encounter semantic variation, we hope that you will practice your linguist skills and ask questions like “in what descriptive ways is my idiolect/dialect different from the one described here?”, “to what extent can meaning vary across languages?”, and “what might this tell us about how meaning can change over time?”. The purpose of this chapter is to highlight interesting semantic patterns within and across languages, rather than to describe the lexicon of any particular person, or to describe the meaning of any particular word.

    Check your understanding

    Query \(\PageIndex{1}\)


    Harley, H. (2017). English words: A linguistic introduction. John Wiley & Sons.

    Murphy, M. L. (2010). Lexical Meaning. Cambridge University Press.

    This page titled 6.2: The mental lexicon is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Catherine Anderson, Bronwyn Bjorkman, Derek Denis, Julianne Doner, Margaret Grant, Nathan Sanders, and Ai Taniguchi (eCampusOntario) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.