The term word denotes the basic unit of a given language. It is simultaneously a semantic, grammatical and phonological unit. In linguistic literature we find many different definitions of a word. The main scientific problems of lexicology are connected with the characteristic features and peculiarities of words and phraseological units as they exist in the vocabulary of present-day English.
That is why we have to clarify some basic concepts pertaining to the problem of a word as a main unit of the language. They are: 1) the problem of defining the word; 2) the connection between words and objects of reality; 3) the motivation of a word since every object of reality possesses a lot of features, but only the most important and characteristic of them may become the representative of the object; 4) the problem of isolation of a word, for the borderline between various linguistic units is not always clear; words of different structural types are characterized by inseparability which finds its expression in graphic, morphological and semantic integrity; 5) the problem of identity of word as the word exists in the language in a system of its grammatical forms (morphological and syntactical).
Being the central element of any language system, the word is a sort of focus for the problems of phonology, lexicology, morphology, syntax and also for some other sciences that have to deal with language and speech, such as philosophy and psychology.
The precise definition of a word is a hard task. There were many attempts to define the word, but all of them are criticized for being incomplete. Any definition of the word is conditioned by the aims and interests of its author.
Linguists have tried to define the word syntactically, semantically, phonologically and by combining various approaches. H. Sweet defined the word as "the minimum sentence" (syntactic approach). E. Sapir takes into consideration the syntactic and semantic aspects. He defines the word as "one of the smallest completely satisfying bits of isolated 'meaning' into which the sentence resolves itself”.
E. Sapir pointed out one more very important characteristic feature of the word, its indivisibility. The indivisibility will be clear from the following examples. If we take a lion and alive. A lion is a word group and we can insert other words between the article a and the word lion: a dead lion, a beautiful lion. Alive is a word, it is indivisible. Nothing can be inserted between its elements.
The well-known French linguist A. Meillet combines the semantic, phonological and grammatical criteria and gives a definition which underlies many definitions suggested both abroad and in our country. He writes: "A word is defined by association of a given meaning with a given group of sounds susceptible of a given grammatical employment".
The weak point of all the definitions of the word is that they do not show the relationship between language and thought. The word is a dialectical unity of form and content in which the form is the spoken or written expression which calls up a specific meaning, whereas the content is the meaning rendering the concept or emotion in the mind of the speaker which he intends to convey to his listener. The system showing a word in all its word-forms is called its paradigm. Each part of speech is characterized by a paradigm of its own. The lexical meaning of a word is the same throughout the paradigm. The grammatical meaning varies from one form to another.
Intralinguistic relations of words are basically of two types: syntagmatic and paradigmatic.
Syntagmatic relations are the relationships that a linguistic unit has with other units in the stretch of language in which it occurs. Syntagmatic relations define the meaning the word possesses when it is used in combination with other words. For example, the meanings of the verb to get can be understood from the following contexts: He got a letter ('to receive'); He got tired ('to become'); So syntagmatic relations are linear (simultaneous) relationships between words.
Paradigmatic relations are the relationships that a linguistic unit has with units by which it may be replaced. Paradigmatic relations exist between words which make up one of the subgroups of vocabulary units, e.g. sets of synonyms, lexico-semantic groups. Paradigmatic relations define the meaning the word possesses through its interrelation with other members of the subgroup in question. For example, the meaning of the verb to get can be fully understood in comparison with other units of the synonymic set: to obtain, to receive, to gain, to acquire, etc. So paradigmatic relations are associative (non-simultaneous) relationships between words.
The term motivation is used to denote the relationship existing between the morphemic or phonemic and structural pattern of the word on the one hand, and its meaning on the other. There are three main types of motivation:
a) phonetical motivation;
b)morphological motivation;
c) semantic motivation.
The phonetical motivation implies a direct connection between the phonetic structure of the word and its meaning. For instance, the word cuckoo (cf. in Russian кукушка) denotes a bird whose call is like its name. Thus, there is a certain similarity between the sound-form of the word and the sounds the bird produces.
The morphological motivation implies a direct connection between the lexical meaning of the component morphemes, the pattern of their arrangement and the meaning of the word. Thus, the main criterion in morphological motivation is the relationship between morphemes. For example, the derived word to rethink is motivated through its morphological structure which suggests the idea of “thinking again”.
The semantic motivation implies a direct connection between the central and marginal meanings of the word. For example, the compound noun eyewash has two meanings: 1) a lotion for the eyes (примочка для глаз); 2) something said or done to deceive a person so that he thinks what he sees is good though in fact it is not (cf. in Russian очковтирательство). The first meaning is based on the literal meanings of the components, i.e. the meanings of the morphemes eye- and -wash. Thus, the motivation of the noun eyewash in its first meaning is morphological. The second meaning of the word eyewash is metaphoric or figurative. In this case the motivation is semantic. Semantic motivation is based on the coexistence of direct and figurative meanings within the semantic structure of the word.
Lexicology has close ties with other branches of linguistics as they also take into account words in one way or another approaching them from different angles.
There is a relationship between lexicology and phonetics since phonetics is also concerned with the study of the word, i.e. with the sound-form of the word. A close connection between lexicologyand grammar is conditioned by the manifold ties between the objects of their study. Even isolated words as presented in a dictionary bear a definite relation to the grammatical system of the language because they belong to some part of speech and conform to some lexico-grammatical characteristics of the word class to which they belong. Lexicology is linked with the history of a language since the latter investigates the changes and the development of the vocabulary of a language. There is also a close relationship between lexicology and stylistics. Stylistics studies many problems treated in lexicology. These are the problems of meaning, synonymy, differentiation of vocabulary according to the sphere of communication and some other issues. Lexicology is bound up with sociolinguistics. Sociolinguistics investigates the extra-linguistic or social causes of the changes in the vocabulary of a language. The word-stock of a language directly and immediately reacts to changes in social life.