Lexical semantics

Lexical semantics (also known as lexicosemantics), as a subfield of linguistic semantics, is the study of word meanings. It includes the study of how words structure their meaning, how they act in grammar and compositionality,

The study of lexical semantics concerns:

the classification and decomposition of lexical items
the differences and similarities in lexical semantic structure cross-linguistically
the relationship of lexical meaning to sentence meaning and syntax.

Lexical units, also referred to as syntactic atoms, can be independent such as in the case of root words or parts of compound words or they require association with other units, as prefixes and suffixes do. The former are termed free morphemes and the latter bound morphemes. They fall into a narrow range of meanings (semantic fields) and can combine with each other to generate new denotations.

Cognitive semantics is the linguistic paradigm/framework that since the 1980s has generated the most studies in lexical semantics, introducing innovations like prototype theory, conceptual metaphors, and frame semantics.

Lexical relations

Lexical items contain information about category (lexical and syntactic), form and meaning. The semantics related to these categories then relate to each lexical item in the lexicon.

Hyponymy and hypernymy

Hyponymy and hypernymy refer to a relationship between a general term and the more specific terms that fall under the category of the general term.

For example, the colors red, green, blue and yellow are hyponyms. They fall under the general term of color, which is the hypernym.

thumb|Taxonomy showing the hypernym "color"

Color (hypernym) → red, green, yellow, blue (hyponyms)

Hyponyms and hypernyms can be described by using a taxonomy, as seen in the example.

Synonym

Synonym refers to words that are pronounced and spelled differently but contain the same meaning.

Happy, joyful, glad (words it occurs with in natural sentences), or whether the meaning is already locally contained in the lexical unit.

In English, WordNet is an example of a semantic network. It contains English words that are grouped into synsets. Some semantic relations between these synsets are meronymy, hyponymy, synonymy, and antonymy.

Semantic fields

How lexical items map onto concepts

First proposed by Trier in the 1930s, semantic field theory proposes that a group of words with interrelated meanings can be categorized under a larger conceptual domain. This entire entity is thereby known as a semantic field. The words boil, bake, fry, and roast, for example, would fall under the larger semantic category of cooking. Semantic field theory asserts that lexical meaning cannot be fully understood by looking at a word in isolation, but by looking at a group of semantically related words. Semantic relations can refer to any relationship in meaning between lexemes, including synonymy (big and large), antonymy (big and small), hypernymy and hyponymy (rose and flower), converseness (buy and sell), and incompatibility. Semantic field theory does not have concrete guidelines that determine the extent of semantic relations between lexemes. The abstract validity of the theory is a subject of debate.

How lexical items map onto events

Event structure is defined as the semantic relation of a verb and its syntactic properties.

Event structure has three primary components:

primitive event type of the lexical item
event composition rules
mapping rules to lexical structure

Verbs can belong to one of three types: states, processes, or transitions.

(1) a. The door is closed. The term generative was proposed by Noam Chomsky in his book Syntactic Structures published in 1957. The term generative linguistics was based on Chomsky's generative grammar, a linguistic theory that states systematic sets of rules (X' theory)can predict grammatical phrases within a natural language. Generative Linguistics is also known as Government-Binding Theory.

Generative linguists of the 1960s, including Noam Chomsky and Ernst von Glasersfeld, believed semantic relations between transitive verbs and intransitive verbs were tied to their independent syntactic organization. Lexicalist theories emphasized that complex words (resulting from compounding and derivation of affixes) have lexical entries that are derived from morphology, rather than resulting from overlapping syntactic and phonological properties, as Generative Linguistics predicts. The distinction between Generative Linguistics and Lexicalist theories can be illustrated by considering the transformation of the word destroy to destruction:

Generative Linguistics theory: states the transformation of destroy → destruction as the nominal, nom + destroy, combined with phonological rules that produce the output destruction. Views this transformation as independent of the morphology.
Lexicalist theory: sees destroy and destruction as having idiosyncratic lexical entries based on their differences in morphology. Argues that each morpheme contributes specific meaning. States that the formation of the complex word destruction is accounted for by a set of Lexical Rules, which are different and independent from syntactic rules. These probing techniques analyzed negative data over prescriptive grammars, and because of Chomsky's proposed Extended Projection Principle in 1986, probing techniques showed where specifiers of a sentence had moved to in order to fulfill the EPP. This allowed syntacticians to hypothesize that lexical items with complex syntactic features (such as ditransitive, inchoative, and causative verbs), could select their own specifier element within a syntax tree construction. (For more on probing techniques, see Suci, G., Gammon, P., & Gamlin, P. (1979)).

This brought the focus back on the syntax-lexical semantics interface; however, syntacticians still sought to understand the relationship between complex verbs and their related syntactic structure, and to what degree the syntax was projected from the lexicon, as the Lexicalist theories argued.

In the mid 1990s, linguists Heidi Harley, Samuel Jay Keyser, and Kenneth Hale addressed some of the implications posed by complex verbs and a lexically-derived syntax. Their proposals indicated that the predicates CAUSE and BECOME, referred to as subunits within a Verb Phrase, acted as a lexical semantic template. Predicates are verbs and state or affirm something about the subject of the sentence or the argument of the sentence. For example, the predicates went and is here below affirm the argument of the subject and the state of the subject respectively.

Lucy went home.

The parcel is here.

The subunits of Verb Phrases led to the Argument Structure Hypothesis and Verb Phrase Hypothesis, both outlined below. The recursion found under the "umbrella" Verb Phrase, the VP Shell, accommodated binary-branching theory; another critical topic during the 1990s. Current theory recognizes the predicate in Specifier position of a tree in inchoative/anticausative verbs (intransitive), or causative verbs (transitive) is what selects the theta role conjoined with a particular verb.

They argue that a predicate's argument structure is represented in the syntax, and that the syntactic representation of the predicate is a lexical projection of its arguments. Thus, the structure of a predicate is strictly a lexical representation, where each phrasal head projects its argument onto a phrasal level within the syntax tree. The selection of this phrasal head is based on Chomsky's Empty Category Principle. This lexical projection of the predicate's argument onto the syntactic structure is the foundation for the Argument Structure Hypothesis.

Halle & Marantz 1993

thumbnail|Halle & Marantz 1993 structure

Morris Halle and Alec Marantz introduced the notion of distributed morphology in 1993. This theory views the syntactic structure of words as a result of morphology and semantics, instead of the morpho-semantic interface being predicted by the syntax. Essentially, the idea that under the Extended Projection Principle there is a local boundary under which a special meaning occurs. This meaning can only occur if a head-projecting morpheme is present within the local domain of the syntactic structure. The following is an example of the tree structure proposed by distributed morphology for the sentence "John's destroying the city". Destroy is the root, V-1 represents verbalization, and D represents nominalization.

Classification of event types

Intransitive verbs: unaccusative versus unergative

The unaccusative hypothesis was put forward by David Perlmutter in 1987, and describes how two classes of intransitive verbs have two different syntactic structures. These are unaccusative verbs and unergative verbs. These classes of verbs are defined by Perlmutter only in syntactic terms. They have the following structures underlyingly:

unaccusative verb: __ [<sub>VP</sub> V NP]

Unergative

b. Mary worked.

In (2a) the verb underlyingly takes a direct object, while in (2b) the verb underlyingly takes a subject.

Transitivity alternations: the inchoative/causative alternation

The change-of-state property of Verb Phrases (VP) is a significant observation for the syntax of lexical semantics because it provides evidence that subunits are embedded in the VP structure, and that the meaning of the entire VP is influenced by this internal grammatical structure. (For example, the VP the vase broke carries a change-of-state meaning of the vase becoming broken, and thus has a silent BECOME subunit within its underlying structure.) There are two types of change-of-state predicates: inchoative and causative.

Inchoative verbs are intransitive, meaning that they occur without a direct object, and these verbs express that their subject has undergone a certain change of state. Inchoative verbs are also known as anticausative verbs. Causative verbs are transitive, meaning that they occur with a direct object, and they express that the subject causes a change of state in the object.

Linguist Martin Haspelmath classifies inchoative/causative verb pairs under three main categories: causative, anticausative, and non-directed alternations. Non-directed alternations are further subdivided into labile, equipollent, and suppletive alternations.

English tends to favour labile alternations, meaning that the same verb is used in the inchoative and causative forms.

b. The knot loosened.

c. Sandy loosened the knot.

In example (4a) we start with a stative intransitive adjective, and derive (4b) where we see an intransitive inchoative verb. In (4c) we see a transitive causative verb.

Marked inchoatives

Some languages (e.g., German, Italian, and French), have multiple morphological classes of inchoative verbs. Generally speaking, these languages separate their inchoative verbs into three classes: verbs that are obligatorily unmarked (they are not marked with a reflexive pronoun, clitic, or affix), verbs that are optionally marked, and verbs that are obligatorily marked. The causative verbs in these languages remain unmarked. Haspelmath refers to this as the anticausative alternation.

For example, inchoative verbs in German are classified into three morphological classes. Class A verbs necessarily form inchoatives with the reflexive pronoun ', Class B verbs form inchoatives necessarily without the reflexive pronoun, and Class C verbs form inchoatives optionally with or without the reflexive pronoun. In example (5), the verb ' is an unmarked inchoative verb from Class B, which also remains unmarked in its causative form. When applied to ditransitive verbs, this hypothesis introduces the structure in diagram (8a). In this tree structure it can be seen that the same path can be traced from either DP to the verb. Tree diagram (7b) illustrates this structure with an example from English. This analysis was a step toward binary branching trees, which was a theoretical change that was furthered by Larson's VP-shell analysis. Sentences with double objects occur with ditransitive verbs, as we can see in the following example:

thumb|Larson's proposed binary-branching VP-shell structure for (9)

(9) a. John sent Mary a package.

b. John sent a package to Mary.

It appears as if the verb send has two objects, or complements (arguments): both Mary, the recipient and parcel, the theme. The argument structure of ditransitive verb phrases is complex and has undergone different structural hypothesis.

The original structural hypothesis was that of ternary branching seen in (9a) and (9b), but following from Kayne's 1981 analysis, Larson maintained that each complement is introduced by a verb.

Following are examples of Larson's tests to show that the hierarchical (superior) order of any two objects aligns with a linear order, so that the second is governed (c-commanded) by the first. In so doing, they also give further evidence of the presence of two VPs where the verb attaches to a causative verb. In examples (14a) and (b), each of the double object constructions are alternated with NP + PP constructions.

(14) a. Satoshi sent Tubingen the Damron Guide. It is the opposite of onomasiology, a branch of lexicology that starts with a concept or object and asks for its name, i.e., "how do you express X?" whereas semasiology starts with a word and asks for its meanings.

The exact meaning of semasiology is somewhat obscure. It is often used as a synonym of semantics. However, semasiology is also sometimes considered part of lexical semantics, a narrow subfield of lexicology (the study of words) and semantics. The term was first used in German by Christian Karl Reisig in 1825 in his work, [Lectures on Latin Linguistics] (), and was used in English by 1847. Semantics replaced it in its original meaning, beginning in 1893.